• Journal of information and communication convergence engineering
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• v.1 no.1
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• pp.27-30
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• 2003

Electrophoretic deposition (EPD) of alcohol YBCO suspensions on the Ag wire electrode is studied. Poly(ethylene glycol) was coordinated to a structure formed by the EPD process with YBCO particles. The suspension is characterized in terms of zeta potential and conductivity. The d.c electric fields of 200-300 V/cm are applied for 1-10 min. The optimal condition for the EPD allows modifying the properties and microstructure of the deposited films. Superconducting coatings with nanometer-sized pores and a preferred orientation along the c-axis were prepared from the result with chemically modified precursor solution. In contrast, YBCO coatings of submicrometer-sized pores and randomly orientated grains were prepared from the solution without PEG.

• Transactions on Electrical and Electronic Materials
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• v.4 no.5
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• pp.6-9
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• 2003

Electrophoretic deposition (EPD) of alcohol YBCO suspensions on the Ag wire electrode is studied. Polyethyleneglycol was coordinated to a structure formed by the EPD process with YBCO particles. The d.c electric fields of 200-300 V/cm are applied for 1-10 min. The optimal condition for the EPD allows modifying the properties and microstructure of the deposited films. Superconducting coatings with nanometer-sized pores and a preferred orientation along the caxis were prepared from the result with chemically modified precursor solution. In contrast, YBCO coatings of submicrometer-sized pores and randomly orientated grains were prepared from the solution without PEG.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.28-36
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• 2011

Diblock copolymers composed of poly(${\varepsilon}$-caprolactone) (PCL) and poly(N,N-dimethylamino-2-ethyl methacrylate) (PDMAEMA), or methoxy polyethylene glycol(PEG), were synthesized via a combination of ring-opening polymerization and atom-transfer radical polymerization in order to prepare polymeric nanoparticles as an antifungal drug carrier. Amphotericin B (AmB), a natural antibiotic, was incorporated into the polymeric nanoparticles. The physical properties of AmB-incorporated polymeric nanoparticles with PCL-b-PDMAEMA and PCL-b-PEG were studied in relation to morphology and particle size. In the aggregation state study, AmB-incorporated PCL-b- PDMAEMA nanoparticles exhibited a monomeric state pattern of free AmB, whereas AmB-incorporated PCL-b- PEG nanoparticles displayed an aggregated pattern. In in vitro hemolysis tests with human red blood cells, AmBincorporated PCL-b-PDMAEMA nanoparticles were seen to be 10 times less cytotoxic than free AmB (5 ${\mu}g$/ml). In addition, an improved antifungal activity of AmBincorporated polymeric nanoparticles was observed through antifungal activity tests using Candida albicans, whereas polymeric nanoparticles themselves were seen not to affect activity. Finally, in vitro AmB release studies were conducted, proving the potential of AmB-incorporated PCL-b-PDMAEMA nanoparticles as a new formulation candidate for AmB.

• Geophysics and Geophysical Exploration
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• v.12 no.4
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• pp.289-298
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• 2009

Optimal data processing parameters were designed to attenuate multiples in seismic data acquired in the south-eastern area of the East Sea, in 2008. Bunch of multiples caused by shallow sea water depth were perceived periodically up to two way travel time of 1,750 ms at every 250 ms over seismic traces. We abbreviated sea bottom multiple as SBM, Peg-leg multiple as PLM, and free-surface multiple as FSM. To attenuate these multiples, seismic data processing flow was constructed including NMO, stack, minimum phase predictive deconvolution filter and wave equation multiple rejections (WEMR). Prevalent multiples were suppressed by predictive deconvolution and remaining multiples were attenuated by WEMR. We concluded that combining deconvolution with WEMR was effective to a seismic data of study area. Derived parameter can be applied to the seismic data processing on adjacent survey area.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.26 no.1
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• pp.199-212
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• 2000

A series of novel ascorbic acid derivatives, polyethoxylated ascorbic acid (PEAA) were synthesized by coupling ascorbic acid with polyethylene glycol (PEG) of two molecular weights (MW: 350 and 550) at the C-2 or C-3 hydroxyl group (2PEAA350, 3PEAA350, 2PEAA550, 3PEAA550) to increase the stability and retain the activity, as a skin whitening agent. Their stability, scavenging activity against free radical, inhibitory activity against tyroxinase and inhibitory activity of melanin synthesis in Bl6 melanoma cell of PEAAs were evaluated in viかo and compared with those of ascorbic acid and 3-O-ethyl ascorbic acid (3OEAA), a Con stable vitamin C derivative. Among PEAAs, 2PEAA350 and 2PEAA550 tad high scaveniging activity against See radical, inhibitory activity against tyrosinase and inhibitory activity if melanogenesis but low stability, 3PEAA350 had high stability and moderate scavenging activity against free radical, infibitory activity against tyrosinase and inhibitory activity of melanogenesis. The stability, scavenging activity against free radical and inhibitory activity of melanogenesis of 3PEAA350 were higher than those of 30EAA. The most stable 3PEAA350 among PEAAs was nontoxic in various toxicological tests. These results suggest that PEAA would be a good whitening agent far enhancing stability and bioavailability.

• Polymer(Korea)
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• v.34 no.3
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• pp.274-281
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• 2010

In this study, PEG-PLA(or PLGA) amphiphilic di-block copolymers were synthesized by ring opening polymerization of D,L-lactide(or glycolide) and applied to polymeric micelle system for solubilization of a rosiglitazone as diabetes drug. The drug could be efficiently loaded into the polymer micelle by solid dispersion technique, and the drug-loaded micelles were characterized and evaluated as a drug delivery carrier by fluorescence spectrometer, DSC, and DLS measurements. The colloidal stability of drug loaded micelles in aqueous media could be enhanced by addition of 2-hydroxy-N-picolylnitinamide as a hydrotropic agent. The polymer micelles also showed biocompatible and nontoxic properties in vitro cell viability using MTT assay, and the drug loaded micelles were observed to be more effective than free drug for decreasing glucose in blood of rats.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.409-412
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• 2013

Curcumin (Cum) has been reported to have potential chemo-preventive and chemotherapeutic activity through influencing various processes, inducing cell cycle arrest, differentiation and apoptosis in a series of cancers. However, the poor solubility of Cum limits its further applications in the treatment of cancer. We have previously reported Cum-loaded nanoparticles (Cum-NPs) prepared with amphilic methoxy poly(ethylene glycol)-polycaprolactone (mPEG-PCL) block copolymers. The current study demonstrated superior antitumor efficacy of Cum-NPs over free Cum in the treatment of lung cancer. In vivo evaluation further demonstrated superior anticancer effects of Cum-NPs by delaying tumor growth compared to free Cum in an established A549 transplanted mice model. Moreover, Cum-NPs showed little toxicity to normal tissues including bone marrow, liver and kidney at a therapeutic dose. These results suggest that Cum-NPs are effective to inhibit the growth of human lung cancer with little toxicity to normal tissues, and could provide a clinically useful therapeutic regimen. They thus merit more research to evaluate the feasibility of clinical application.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.40-49
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• 1998

Protoplasts were isolated from mesophyll of tobacco(Nicotiana glauca) transformed with kanamycin-resistant gene (NPT II gene) and potato hairy root callus containing Ri plasmid of Agrobacterium rhiEogenes, and protoplasm fusion was made between the isolated protoplasts. The transgenic tobacco leaf tissue could grow on the media containing high concentrations of kanamycin, but not on the phytohormone-free media. On the other hand, the potato hairy root calli could be cultured on the phytohormone-free media but not on media containing more than 40 ㎍/ml kanamycin. In these conditions, the viability of both protoplasts were above 90%, These selection markers were used for the selection of protoplasts fused between the two, i.e. protoplast fusion was detected using selection media containing 100㎍/ml kanamycin and with no phytohormone. The mixture of 1.0% cellulase, 0.3% macerozyme, and 0.7M mannitol was best for the maximum protoplast production for tobacco, and that of 2.0% cellulase, 2.0% macerozyme, 1.0% dricelase, and 0.5M mannitol for potato. Both tobacco mesophyll and potato callus protoplasts were fused by using PEG solution on the selectable medium. Cell walls were regenerated after 5 days in this medium, and colonies were alive until 4 weeks after cultural, but died after 6 weeks.

• Analytical Science and Technology
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• v.8 no.4
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• pp.865-868
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• 1995

The method of matrix-assisted laser desorption ionization mass spectrometry has been used to solve some bioanalytical problems, which is difficult to analyse by general methods. For the selection of proper laser wavelength and matrices, eight matriees was used with laser wavelength of 226 and 355nm. The result shows that with wavelength of 355nm better results could be obtained with most of the matrices. The molecular weight of eytochrome C, which was seperated by gel electrophoresis and electro-blotted onto NC membrane is determined by MALDI. The accuracy is better than 0.1%, which is much higher than that of SDS-PAGE. Protein mixture extracted from crude peanut oil is directly determined by MALDI. The molecuiar weight of its three components are determined, and the result also demonstrated that these proteins are in free manner. As proteins arc in 2S bond, with the traditional method, SDS-PAGE, it is not able to decide whether protein exists in combination mode or in free manner. In the technique of two phase aquesous solution, which is used for separating biomaterials, water soluble polymers stained with dyes are used in this technique. By the use of MALDI the number or the dye molecules react with the polymer PEG molecule are determined, and that is difficult to determined by other methods.

• Archives of Reconstructive Microsurgery
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• v.3 no.1
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• pp.81-89
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• 1994

Firstly the wrap-around free flap from the great toe was transferred successfully by Morrison and O'Brien in 1980 for reconstruction in chronic case of amputated thumb distal to the MP joint. Since then, significant bone peg resorption and grafted bone fracture have been reported in most of cases after operation. We have performed thumb reconstructions within 2 weeks after injury in 11 cases which included acute crushing injuries or failed replantation of thumb at Guro Hospital from September, 1983 to October, 1993. The results obtained from this study are as follows: 1. There were 8 males and 3 females and the mean age was 28.8 years old ranged from 3 years old to 50 years old. 2. The most common injury mechanism was machinary injury in 10 of 11 cases. 3. We have performed thumb reconstructions by using wrap-around free flap from the great toe without bone graft in 6 cases and with bone graft in 5 cases within 2 weeks after injury. 4. During 6 years and 1 month mean follow-up period, there were bone resorptions in 3, grafted bone fracture in 1, infections in 2 and soft tissue necrosis in 3 cases. 5. We obtained satisfactable results in respect of function and cosmesis and urged to use this flap for reconstruction in acute thumb injury.