• Journal of Microbiology and Biotechnology
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• v.25 no.8
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• pp.1227-1233
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• 2015

Vascular endothelial growth factor (VEGF) plays a key role in angiogenesis through binding to its specific receptors, which mainly occurs to VEGF receptor 2 (VEGFR-2), a kinase insert domain-containing receptor. Therefore, the disruption of VEGFR-2 signaling provides a promising therapeutic approach for the treatment of cancer by inhibiting abnormal or tumorinduced angiogenesis. To explore this potential, we expressed the catalytic domain of VEGFR-2 (VEGFR-2-CD) as a soluble active kinase in Escherichia coli. The recombinant protein was purified and the VEGFR-2-CD activity was investigated. The obtained VEGFR-2-CD showed autophosphorylation activity and phosphate transfer activity comparable to the commercial enzyme. Furthermore, the IC₅₀ value of known VEGFR-2 inhibitor was determined using the purified VEGFR-2-CD. These results indicated a possibility for functional and economical VEGFR-2-CD expression in E. coli to use for inhibitor screening.

• Journal of Environmental Science International
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• v.16 no.12
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• pp.1431-1437
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• 2007

Cobalt titanates($CoTiO_x$), such as $CoTiO_3$ and $Co_2TiO_4$, have been synthesized via a solid-state reaction and characterized using X-ray diffraction(XRD) and X-ray photoelectron spectroscopic(XPS) measurement techniques, prior to being used for continuous wet trichloroethylene(TCE) oxidation at $36^{\circ}C$, to support our earlier chemical structure model for Co species in 5 wt% $CoO_x/TiO_2$(fresh) and(spent) catalysts. Each XRD pattern for the synthesized $CoTiO_3$ and $Co_2TiO_4$ was very close to those obtained from the respective standard XRD data files. The two $CoTiO_x$ samples gave Co 2p XPS spectra consisting of very strong main peaks for Co $2p_{3/2}$ and $2p_{1/2}$ with corresponding satellite structures at higher binding energies. The Co $2p_{3/2}$ main structure appeared at 781.3 eV for the $CoTiO_3$, and it was indicated at 781.1 eV with the $Co_2TiO_4$. Not only could these binding energy values be very similar to that exhibited for the 5 wt% $CoO_x/TiO_2$(fresh), but the spin-orbit splitting(${\Delta}E$) had also no noticeable difference between the cobalt titanates and a sample of the fresh catalyst. Neither of all the $CoTiO_x$ samples were active for the wet TCE oxidation, as expected, but a sample of pure $Co_3O_4$ had a good activity for this reaction. The earlier proposed model for the surface $CoO_x$ species existing with the fresh and spent catalysts is very consistent with the XPS characterization and activity measurements for the cobalt titanates.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.428-429
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• 2011

Recently, we performed ab initio total energy calculation and tight-binding molecular dynamics (TBMD) simulation to study structures and the reconstruction of native defects in graphene. In the previous study, we predicted by TBMD simulation that a double vacancy in graphene is reconstructed into a 555-777 composed of triple pentagons and triple heptagons [1]. The structural change from pentagon-octagon-pentagon (5-8-5) to 555-777 has been confirmed by recent experiments [2,3] and the detail of the reconstruction process is carefully studied by ab initio calculation. Pentagon-heptagon (5-7) pairs are also found to play an important role in the reconstruction of vacancy in graphene and single wall carbon nanotube [4]. In the TBMD simulation of graphene nanoribbon (GNR), we found the evaporation of carbon atoms from both the zigzag and armchair edges is preceded by the formation of heptagon rings, which serve as a gateway for carbon atoms to escape. In the simulation for a GNR armchair-zigzag-armchair junction, carbon atoms are evaporated row-by-row from the outermost row of the zigzag edge [5], which is in excellent agreement with recent experiments [2, 6]. We also present the recent results on the formation and development of dislocation in graphene. It is found that the coalescence of 5-7 pairs with vacancy defects develops dislocation in graphene and induces the separation of two 5-7 pairs. Our TBMD simulations also show that adatoms are ejected and evaporated from graphene surface due to large strain around 5-7 pairs. It is observed that an adatom wanders on the graphene surface and helps non-hexagonal rings change into stable hexagonal rings before its evaporation.

• Journal of the Korea Society of Computer and Information
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• v.26 no.2
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• pp.1-9
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• 2021

In this paper, we extend a generic library framework based on the state monad to exploit deterministic parallelism in a purely functional language Haskell and provide benchmarks for the extended features on a multicore machine. Although purely functional programs are known to be well-suited to exploit parallelism, unintended squential data dependencies could prohibit effective parallelism. Symbolic execution programs usually implement fresh name generation in order to prevent confusion between variables in different scope with the same name. Such implementations are often based on squential state management, working against parallelism. We provide reusable primitives to help developing parallel symbolic execution programs with unbound-genercis, a generic name-binding library for Haskell, avoiding sequential dependencies in fresh name generation. Our parallel extension does not modify the internal implementation of the unbound-generics library, having zero possibility of degrading existing serial implementations of symbolic execution based on unbound-genecrics. Therefore, our extension can be applied only to the parts of source code that need parallel speedup.

• Journal of Arbitration Studies
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• v.20 no.2
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• pp.173-198
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• 2010

The purpose of this paper is to research on the liability for the space damage and the settlement of the dispute with reference to the space activity under the international space treaty and national space law of Korea. The United Nations has adopted five treaties relating to the space activity as follows: The Outer Space Treaty of 1967, the Rescue and Return Agreement of 1968, the Liability Convention of 1972, the Registration Convention of 1974, and the Moon Treaty of 1979. All five treaties have come into force. Korea has ratified above four treaties except the Moon Treaty. Korea has enacted three national legislations relating to space development as follows: Aerospace Industry Development Promotion Act of 1987, Outer Space Development Promotion Act of 2005, Outer Space Damage Compensation Act of 2008. The Outer Space Treaty of 1967 regulates the international responsibility for national activities in outer space, the national tort liability for damage by space launching object, the national measures for dispute prevention and international consultation in the exploration and use of outer space, the joint resolution of practical questions by international inter-governmental organizations in the exploration and use of outer space. The Liability Convention of 1972 regulates the absolute liability by a launching state, the faulty liability by a launching state, the joint and several liability by a launching state, the person claiming for compensation, the claim method for compensation, the claim period of compensation, the claim for compensation and local remedy, the compensation amount for damage by a launching state, the establishment of the Claims Commission. The Outer Space Damage Compensation Act of 2008 in Korea regulates the definition of space damage, the relation of the Outer Space Damage Compensation Act and the international treaty, the non-faulty liability for damage by a launching person, the concentration of liability and recourse by a launching person, the exclusion of application of the Product Liability Act, the limit amount of the liability for damage by a launching person, the cover of the liability insurance by a launching person, the measures and assistance by the government in case of occurring the space damage, the exercise period of the claim right of compensation for damage. The Liability Convention of 1972 should be improved as follows: the problem in respect of the claimer of compensation for damage, the problem in respect of the efficiency of decision by the Claims Commission. The Outer Space Damage Compensation Act of 2008 in Korea should be improved as follows: the inclusion of indirect damage into the definition of space damage, the change of currency unit of the limit amount of liability for damage, the establishment of joint and several liability and recourse right for damage by space joint launching person, the establishment of the Space Damage Compensation Review Commission. The 1998 Final Draft Convention on the Settlement of Disputes Related to Space Activities of 1998 by ILA regulates the binding procedure and non-binding settlement procedure for the disputes in respect of space activity. The non-binding procedure regulates the negotiation or the peaceful means and compromise for dispute settlement. The binding procedure regulates the choice of a means among the following means: International Space Law Court if it will be established, International Court of Justice, and Arbitration Court. The above final Draft Convention by ILA will be a model for the innovative development in respect of the peaceful settlement of disputes with reference to space activity and will be useful for establishing the frame of practicable dispute settlement. Korea has built the space center at Oinarodo, Goheung Province in June 2009. Korea has launched the first small launch vehicle KSLV-1 at the Naro Space Center in August 2009 and June 2010. In Korea, it will be the possibility to be occurred the problems relating to the international responsibility and dispute settlement, and the liability for space damage in the course of space activity. Accordingly the Korean government and launching organization should make the legal and systematic policy to cope with such problems.

• Journal of Navigation and Port Research
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• v.27 no.3
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• pp.321-327
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• 2003

The Memorandum of Understanding (MOU) is the document of intent signed between the Port States Control(PSC) to undertake a uniform as agreed. Though the MOU is not a legally binding, in case where the agreed items are violated without a just cause, the denunciation will follow. International Maritime Organization (IMO) and regional MOUs have been making amendments and reinforcing the relevant requirements, so that port State Authorities can effectively eradicate the substandard vessels. However, the various problems have arisen due to the existence of different requirements of each MOU, the lack of information exchange between each MOU, the lack of uniform PSC implementation within the same MOU and the lack of adequate system due to the short history of MOUs. In this paper, the MOU records for three years (1999∼2001) were analyzed according to each MOU, type of ship, deficiency code, classification society, the number of inspected ships and the number of detained ships to assess the problems (Statistics during 2002 will be published after August 2003). The purpose of this study is to help better understand the PSC activities within each MOU and to establish effective countermeasures by grasping the problems that exist in the PSC at present.

• BMB Reports
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• v.40 no.4
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• pp.547-553
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• 2007

Many motifs along the 1.2 kb myostatin promoter (MSTNpro) in sheep have been found by the MatInspecter program in our recent study. To further verify the role of the motifs and better understand the transcriptional regulation mechanism of the myostatin gene in sheep, the reporter gene EGFP (enhanced green fluorescent protein) was selected and the wild-type (W) vector MSTNPro$^W$-EGFP or motif-mutational (M) vector MSTNPro$^M$-EGFP were constructed. The transcriptional regulation activities were analyzed by detecting the fluorescence strength of EGFP in C2C12 myoblasts transfected with the vectors. The results showed that E-box (E) 3, E4, E5 and E7, particularly E3, E5 and E7, had important effects on the activity of the 1.2 kb sheep myostatin promoter. In addition, we also detected several other important motifs such as MTBF (muscle-specific Mt binding factor), MEF2 (myocyte enhancer factor 2), GRE (glucocorticoid response elements) and PRE (progesterone response elements) along the sheep myostatin promoter by the mutational analysis.

• BMB Reports
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• v.42 no.11
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• pp.725-730
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• 2009

Cyclin E1 (CCNE1), a positive regulator of the cell cycle, controls the transition of cells from G1 to S phase. In numerous human tumors, however, CCNE1 expression is frequently dysregulated, while the mechanism leading to its dysregulation remains incompletely defined. Herein, we showed that CCNE1 expression was subject to post-transcriptional regulation by a microRNA miR-16-1. This was evident at protein level of CCNE1 as well as its mRNA level. Further evident by dual luciferase reporter assay revealed that two evolutionary conserved binding sites on 3' UTR of CCNE1 were the direct functional target sites. Moreover, we showed that miR-16-1 induced G0/G1 cell cycle arrest by targeting CCNE1 and siRNA against CCNE1 partially phenocopied miR-16-1-induced cell cycle phenotype whereas substantially rescued anti-miR-16-1- induced phenotype. Together, all these results demonstrate that miR-16-1 plays a vital role in modulating cellular process in human cancers and indicate the therapeutic potential of miR-16-1 in cancer therapy.

• Analytical Science and Technology
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• v.24 no.6
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• pp.460-466
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• 2011

The activity of an antimicrobial peptide, magainin 2, on lipid membranes was investigated using solid-state NMR and a new sampling method that employed mechanically aligned bilayers between thin glass plates. The experiments were performed at two hydration levels. At 95% hydration about 15% of the lipid bilayers were disrupted and at full hydration 20% were disrupted. From the comparison of two equilibrium states established by two sampling methods the importance of peptide binding to the lipid bilayer for whole membrane disruption was demonstrated.

• BMB Reports
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• v.44 no.3
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• pp.187-192
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• 2011

TGF-$\beta$ activated kinase-1 (TAK1) plays a pivotal role in developmental processes in many species. Previous research has mainly focused on the function of TAK1 in model organisms, and little is known about the function of TAK1 in hymenoptera insects. Here, we isolated and characterized the TAK1 gene from Apis cerana cerana. Promoter analysis of AccTAK1 revealed the presence of transcription factor binding sites related to early development. Real-time quantitative PCR and immunohistochemistry experiments revealed that AccTAK1 was expressed at high levels in fourth instar larvae, primarily in the abdomen, in the intestinal wall cells of the midgut and in the secretory cells of the salivary glands. In addition, AccTAK1 expression in fourth instar larvae could be dramatically induced by treatment with pesticides and organic solvents. These observations suggest that AccTAK1 may be involved in the regulation of early development in the larval salivary gland and midgut.