• BMB Reports
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• v.33 no.6
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• pp.476-482
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• 2000

In this paper, we report a new cationic lipid composed of L-lysinamide and cholesterol as a potent gene delivery vector. $3{\beta}$[L-Lysinamide-carbamoyl] cholesterol could self-assemble with plasmid DNA forming discrete lipoplexes. From atomic force microscopic images of the complexes, the size distribution was observed to range from 100 to 150 nm in diameter. The transfection efficiency of this amphiphile on different cell lines was evaluated as a micellar solution in the absence of the fusogenic helper lipid, dioleoyl phosphatidyletbanolamine (DOPE). Transfection experiments were performed as a function of charge ratio (lipid/DNA) and transfection time. Cytotoxicity and in vitro transfection efficiency of the amphiphile was demonstrated and compared with those of commercially available Lipofectin and polyethylenimine (PEI).

• Proceedings of the KIEE Conference
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• 2002.11a
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• pp.263-265
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• 2002

We have used the secondary-step immobilization methods based on the chip pattern of hydrophobic self-assembly layers to assemble microfabricated particles onto the chip pattern. Immobilization of DNA, fabrication of the particles and the chip pattern, arrangement of the particles on the chip pattern, and recognition of each using DNA fluorescence measurement were carried out. Establishing the walls, the arrangement stability of the particles was improved. Each DNA is able to distinguish by using the lithography process on the particles. Advantages of this method are process simplicity, wide applicability and stability. It is thought that this method can be applicable as a new fabrication technology to develop a minute integration type biosensor microarray.

• Korean Journal of Materials Research
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• v.18 no.12
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• pp.664-668
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• 2008

Vapor phase polymerization of a conductive polymer on a $SiO_2$ surface can offer an easy and convenient means to depositing pure and conductive polymer thin films. However, the vapor phase deposition is generally associated with very poor adhesion as well as difficulty when patterning the polymer thin film onto an oxide dielectric substrate. For a significant improvement of the patternability and adhesion of Poly(3-hexylthiophene) (P3HT) thin film to a $SiO_2$ surface, the substrate was pre-patterned with n-octadecyltrichlorosilane (OTS) molecules using a ${\mu}$-contact printing method. The negative patterns were then backfilled with each of three amino-functionalized silane self-assembled monolayers (SAMs) of (3-aminopropyl) trimethoxysilane (APS), N-(2-aminoethyl)-aminopropyltrimethoxysilane (EDA), and (3- trimethoxysilylpropyl)diethylenetriamine (DET). The quality and electrical properties of the patterned P3HT thin films were investigated with optical and atomic force microscopy and a four-point probe. The results exhibited excellent selective deposition and significantly improved adhesion of P3HT films to a $SiO_2$ surface. In addition, the conductivity of polymeric thin films was relatively high (${\sim}13.51\;S/cm$).

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.558-564
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• 2013

A simple and effective method is introduced to synthesize a series of polystyrene-b-poly(oligo(ethylene oxide) monomethyl ether methacrylate)-b-polystyrene (PSt-b-POEOMA-b-PSt) triblock copolymers. The structures of PSt-b-POEOMA-b-PSt copolymers were characterized by Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance ($^1H$ NMR) spectroscopy. The molecular weight and molecular weight distribution of the copolymer were measured by gel permeation chromatography (GPC). Furthermore, the self-assembling and drug-loaded behaviours of three different ratios of PSt-b-POEOMA-b-PSt were studied. These copolymers could readily self-assemble into micelles in aqueous solution. The vitamin E-loaded copolymer micelles were produced by the dialysis method. The micelle size and core-shell structure of the block copolymer micelles and the drug-loaded micelles were confirmed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The thermal properties of the copolymer micelles before and after drug-loaded were investigated by different scanning calorimetry (DSC). The results show that the micelle size is slightly increased with increasing the content of hydrophobic segments and the micelles are still core-shell spherical structures after drug-loaded. Moreover, the glass transition temperature (Tg) of polystyrene is reduced after the drug loaded. The drug loading content (DLC) of the copolymer micelles is 70%-80% by ultraviolet (UV) photolithography analysis. These properties indicate the micelles self-assembled from PSt-b-POEOMA-b-PSt copolymers would have potential as carriers for the encapsulation of hydrophobic drugs.

• Korean Chemical Engineering Research
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• v.46 no.1
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• pp.1-6
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• 2008

Block copolymers spontaneously assemble into various nanoscale structures such as spheres, cylinders, and lamellar structures according to the relative volumn ratio of each macromolecular block and their overall molecular weights. The self-assembled structures of block copolymer have been extensively investigated for the applications such as nanocomposites, photonic crystals, nanowires, magnetic-storage media, flash memory devices. However, the naturally formed nanostructures of block copolymers contain a high density of defects such that the practical applications for nanoscale devices have been limited. For the practical application of block copolymer nanostructures, a robust process to direct the assembly of block copolymers in thin film geometry is required to be established. To exploit self-assembly of block copolymer for the nanotechnology, it is indispensible to fabricate defect-free self-assembled nanostructure over an arbitrarily large area.

• Journal of the Korean Ceramic Society
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• v.50 no.1
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• pp.1-17
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• 2013

Since their first discovery, carbon nanotubes (CNTs) have become a material central to the field of nanotechnology. Owing to their splendid physical, structural and chemical properties, they have the potential to impact a wide range of applications, including advanced ceramics, nanoelectronic devices, nanoscale sensors, solar cells, battery electrodes, and field emitters. This review summarizes the synthetic methods of preparing CNTs and focuses on the chemical vapor deposition (CVD) method, especially catalytic CVD. In order to stabilize and disperse the catalyst nanoparticles (NPs) during synthesis, zeolite was implemented as the template to support metal-containing NPs, so that both CNTs in the bulk and on a 2D substrate were successfully synthesized. Despite more challenges ahead, there is always hope for widespread ever-new applications for CNTs with the development of technology.

• BMB Reports
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• v.49 no.11
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• pp.629-634
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• 2016

Transmembrane and coiled-coil domain family 3 (TMCC3) has been reported to be expressed in the human brain; however, its function is still unknown. Here, we found that expression of TMCC3 is higher in human whole brain, testis and spinal cord compared to other human tissues. TMCC3 was expressed in mouse developing hind brain, lung, kidney and somites, with strongest expression in the mesenchyme of developing tongue. By expression of recombinant TMCC3 and its deletion mutants, we found that TMCC3 proteins self-assemble to oligomerize. Immunostaining and confocal microscopy data revealed that TMCC3 proteins are localized in endoplasmic reticulum through transmembrane domains. Based on immunoprecipitation and mass spectroscopy data, TMCC3 proteins associate with TMCC3 and 14-3-3 proteins. This supports the idea that TMCC3 proteins form oligomers and that 14-3-3 may be involved in the function of TMCC3. Taken together, these results may be useful for better understanding of uncharacterized function of TMCC3.

• Journal of Engineering Education Research
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• v.26 no.1
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• pp.37-44
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• 2023

Recently, the Internet of Things is attracting attention as an important key technology of the 4th Industrial Revolution, and SW education using physical computing is suggested as a good alternative to supplement the problems raised by beginners in programming education. Among the many teaching tools that can be used for physical computing education, MODI is a modular manufacturing tool that anyone can easily assemble like Lego. MODI is a teaching tool that can improve learners' achievement by linking a self-linked block-type code editor called MODI Studio to lay the foundation for programming in a relatively small amount of time and immediately check the results in person. In this paper, a physical computing education method using MODI was designed to be applied to basic programming courses for programming beginners and applied to after-school classes for middle school students. As a result, it was found that students' interest and satisfaction were much higher in physical computing classes using MODI than in text-based programming classes. It can be seen that physical computing education that allows beginners to see and feel the results in person is more effective than grammar-oriented text programming, and it can have a positive effect on improving basic programming skills by increasing students' participation.

• Journal of Families and Better Life
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• v.28 no.6
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• pp.19-34
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• 2010

This study aims to describe actual condition of residents' involvement of Sk$\"{a}$rk$\"{a}$ll ecovillage in Sweden by in-depth interviews with five residents. This study, hopefully, could contribute to offer useful information for forming ecovillage, as well as awakening about ecovillage movement to the public in Korea. The interviews were fulfilled during spring of 2010 in G$\"{o}$teborg and Sk$\"{a}$rk$\"{a}$ll ecovillage in Sweden. The results are as follows: 1) In terms of overall residents' involvement by self-evaluation everybody agrees with that residents' involvement was quite excellent during forming stage of the village, while it has been notably decreased now in running stage. It reveals there is a gap between ideology and reality. 2) Concerning decision making method, they use majority decision instead of consensus, since only 9 households of 20 are residing there all year around, it is hardly possible to assemble all the residents in the meeting. In Accordance with problematic conflicts in the village recently, development of socialization with others and education of communication skill for residents probably could be helpful to resolve conflicts among residents in long term. 3) In terms of evaluation of ecovillage movement in Sk$\"{a}$rk$\"{a}$ll ecovillage, it is the fact that many residents live less self-sufficiently, more energy consumed than the ideology pursuits. Also, they live with close connections with conventional society. Nevertheless, the efforts they are willing to practice 3R principles (Recycle, Reuse, Reduction) have to be highly respected, if we consider its educational influence to environmental movement for the conventional society.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.8 no.1
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• pp.37-44
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• 2015

In this paper, we have investigated a selective assembly method of single-walled carbon nanotubes (SWCNTs) on a silicon substrate using only photolithographic process and then proposed a fabrication method of field effect transistors (FETs) using SWCNT-based patterns. The aminopropylethoxysilane (APTES) patterns, which are formed for positively charged surface molecular patterns, are utilized to assemble and align millions of SWCNTs and we can more effectively assemble on a silicon (Si) surface using this method than assembly processes using only the 1-octadecyltrichlorosilane (OTS). We investigated a selective assembly method of SWCNTs on a Si surface using surface-programmed APTES and OTS patterns and then a fabrication method of FETs. photoresist(PR) patterns were made using photolithographic process on the silicon dioxide (SiO2) grown Si substrate and the substrate was placed in the OTS solution (1:500 v/v in anhydrous hexane) to cover the bare SiO2 regions. After removing the PR, the substrate was placed in APTES solution to backfill the remaining SiO2 area. This surface-programmed substrate was placed into a SWCNT solution dispersed in dichlorobenzene. SWCNTs were attracted toward the positively charged molecular regions, and aligned along the APTES patterns. On the contrary, SWCNT were not assembled on the OTS patterns. In this process, positively charged surface molecular patterns are utilized to direct the assembly of negatively charged SWCNT on SiO2. As a result, the selectively assembled SWCNT channels can be obtained between two electrodes(source and drain electrodes). Finally, we can successfully fabricate SWCNT-based multi-channel FETs by using our self-assembled monolayer method.