• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.3
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• pp.277-285
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• 1986

A total of 16 varieties from Korea and Indonesia were tested at Suwon, Korea (126$^{\circ}$19'E, 37$^{\circ}$16'N and 37m above sea level) and Bali, Indonesia (115$^{\circ}$ 14'E, 8$^{\circ}$42'S and 10m above sea level). Japonica-type varieties showed pre-matured heading at Bali, tropical zone, while Bulu varieties showed no heading at Suwon, temperate zone. The varieties of Indica-type and Ind./Jap. showed faster heading in tropical zone than in temperate zone. Dry matter of the varieties weighed more difference among varietal groups in tropical than in temperate area, while plant height responsed differently depending on variety and test region.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.161-161
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• 2017

Seed endophytes are very remarkable groups of bacteria for their unique abilities of being vertically transmitted and conserved. As plants attain hybrid vigor and heterosis in the process of crossbreeding, this might also lead to the changes in the community structure and diversity of plant endophytes in the hybrid plants ultimately affecting the endophytes of the seeds. It would be interesting to characterize how seed endophyte composition change over time. The objective of this study is to gain insights into the influence of natural crossbreeding and parental lineage in the seed bacterial endophytic communities of two pure inbred lines exploring contributions of the two most important sources of plant endophytes - colonization from external sources and vertical transmission via seeds. Total genomic DNA was isolated from rice seeds and bacterial DNA was selectively amplified by PCR. The diversity of endophytic bacteria was studied through Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis. Diversity between the original parents and the pure inbred line may show significant differences in terms of richness, evenness and diversity indices. Heat maps reveal astonishing contributions of both or either parents (IR29 ${\times}$ Pokkali and AT401 ${\times}$ IR31868) in the shaping of the bacterial seed endophytes of the hybrid, FL478 and IC32, respectively. Most of the T-RFs of the subsequent pure inbred line could be traced to any or both of the parents. Comparison of common and genotype-specific T-RFs of parents and their offspring reveals that majority of the T-RFs are shared suggesting higher transmission of bacterial communities common to both parents. The parents influence the bacterial community of their offspring. Unique T-RFs of the offspring also suggest external sources of colonization particularly as the seeds are cultivated in different ecogeographical locations. This study showed that host parental lines contributed greatly in the shaping of bacterial seed endophytes of their offspring. It also revealed transmission and potential conservation of core seed bacterial endophytes that generally become the dominant microbiota in the succeeding generations of plant hosts.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.2
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• pp.167-172
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• 2004

In the human skin, vitamin C (L -ascorbic acid) that is well known as the activated materials has effects that is skin anti-aging and wrinkle repair by giving impetus to collagen biosynthesis and anti-oxidation, and that is the sun screen, a wound recovering, inhibition melanogenesis and so on. In spite of its effects, vitamin C has the defects of the skin stimulation and easily oxidized instability by water, air, heat and light. For solving their matters, many investigation is advanced and its results are synthesized the various vitamin C derivatives. And yet they have not solved the unstable property of vitamin C and were still insufficient for the comparing with the effect of the pure vitamin C itself. In this study, in order to prepare vitamin C derivative of being improved the stability and to apply vitamin C effect in the skin, we prepared new vitamin C derivative, phytosphingosine ascorbate, by using phytosphingosine, one of sphingolipids, which have a distinguished skin affinity. Phytosphingosine ascorbate can be prepared as the ionic bond between amine group (-NH$_2$) of phytosphingosine and hydroxy group (-OH) of vitamin C by way of the relatively simple reaction. So the structure and properties of the synthesized phytosphingosine ascorbate was confirmed the use of elemental analysis (C 58.3 : H 9.3 : N 2.8 : O 29.5), MALDI TOF-MS (Mw=492.58), Ultraviolet spectra (268.5nm), lH NMR, FT-IR spectra, thermal analysis (m.p=l54$^{\circ}C$), HPLC and so on. And we could confirm the anti-bacterial and anti-oxidation effects. Based on these results, we could confirm to prepare a new material that was expected of both effects of vitamin C and phytosphingosine and that is improved properties of vitamin C.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.21-29
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• 1998

The rare-earth orthoborate family, RM3(BO3)4 is known to be the most promising material for the microlaser host. To grow LaSc3(BO3)4 single crystal, the phase relation of the system LaBO3-ScBO3 was investigated by DTA method. LaSc(BO3)4 was the unique intermediate compound in the binary system the peritectic reaction point of which was 1495 ±2℃. Owing to the peritectic behavior of the compound, the crystal growth of the rare-earth Sc-borate was carried out by pulling from the melt-soultion of La1+xSc3-x(BO3)4. The optimal conditions for the growth of LaSc3(BO3)4 were determined by traditional CZ method : pulling speed 0.7mm/hr, rotation speed 7-10 rpm under reduction condition. Pt and Ir crucibles could be used for about 8-10 times of growth. The effect of thermal configurations on the temperature distribution was investigated. A special two-coordinate manipulator was made for the precise movement of thermocouples from the melt to the top of the furnace for several thermal configurations. The radial gradient on the melt surface depends strongly on the construction of the afterheater. On the other hand, the axial gradient was mainly propotional to both the opening degree of baffle plate and the mutual positions of crucible and heater.

• Polymer(Korea)
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• v.29 no.1
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• pp.74-80
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• 2005

To use the filter materials for reduction of carbonyl compounds in cigarette mainstream smoke, the bead type cation and anion exchangers were synthesized by the suspension polymerization of GMA and DVB followed by the subsequent functionalization with sodium sulfite and diethylamine, respectively. FT-IR/ATR was used to characterize functionalized copolymer formation by sulfonation and amination, and the morphology change of ion exchangers according to the adsorption of cigarette mainstream smoke were observed by SEM. Ion exchange capacity, functionalization yield and adsorption properties of carbonyl compounds in cigarette mainstream smoke were investigated. The highest functionalization yields and ion exchange capacity were obtained at 5 wt% DVB content in co-monomer. The adsorption amount of carbonyl compounds in cigarette mainstream smoke of anion exchanger was higher than that of cation exchanger because of its electron delocalization in carbonyl group. The adsorption efficiency was increased in the presence of moisture. This results indicated that the anion exchanger was applicable for cigarette filter material because of its large ion exchange capacity and rapid ion exchange reaction.

• Polymer(Korea)
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• v.29 no.1
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• pp.36-40
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• 2005

Poly(amino acid) derivatives have been widely investigated as a drug carrier in drug delivery system. Particularly,polysuccinimide (PSI) is one of the most promising drug carriers since it possesses suitable physicochemical characteristics for development of macromolecular prodrugs, due to biocompatibility and biodegradability. In this study, we deal with the synthesis of polyaspartamide having various functional groups such as methoxy-poly(ethylene glycol) (MPEG) via ring closing of PSI. PSI was synthesized by polyonensation polymerization of spartic acid. The variety of average molecular weight was confirmed with reacion time and catalyst content to observe the optimum condition of synthesis. MPEG, hydrophilic chain, was bonded to fabricate polymeric micell composed of hydrophilic and hydrophobic polymer. All materials were characterized by 1H-NMR, FT-IR and GPC. In addition, the formation of nanoparticle micelle as drug carrier were also examined. Micelle size was measured by ELS and AFM. The functionalized polysparamide formed nanoparticle micelle whose size ranged from 90 to 130 nm. In conclusion, we prepared polyaspartamide functionalized with PEG examined the possibility as drug carriers.

• Radiation Oncology Journal
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• v.26 no.4
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• pp.195-203
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• 2008

Purpose: To investigate the treatment outcome and failure patterns after definitive chemoradiation therapy in locally advanced, unresectable esophageal cancer. Materials and Methods: From February 1994 to December 2002, 168 patients with locally advanced unresectable or medically inoperable esophageal cancer were treated by definitive chemoradiation therapy. External beam radiation therapy (EBRT) ($42{\sim}46\;Gy$) was delivered to the region encompassing the primary tumor and involved lymph nodes, while the supraclavicular fossa and celiac area were included in the treatment area as a function of disease location. The administered cone-down radiation dose to the gross tumor went up to $54{\sim}66\;Gy$, while the fraction size of the EBRT was 1.8-2.0 Gy/fraction qd or 1.2 Gy/fraction bid. An optional high dose rate (HDR) intraluminal brachytherapy (BT) boost was also administered (Ir-192, $9{\sim}12\;Gy/3{\sim}4\;fx$). Two cycles of concurrent FP chemotherapy (5-FU $1,000\;mg/m^2$/day, days $2{\sim}6$, $30{\sim}34$, cisplatin $60\;mg/m^2$/day, days 1, 29) were delivered during radiotherapy with the addition of two more cycles. Results: One hundred sixty patients were analyzable for this review [median follow-up time: 10 months (range $1{\sim}149$ months)). The number of patients within AJCC stages I, II, III, and IV was 5 (3.1%), 38 (23.8%), 68 (42.5%), and 49 (30.6%), respectively. A HDR intraluminal BT was performed in 26 patients. The 160 patients had a median EBRT radiation dose of 59.4 Gy (range $44.4{\sim}66$) and a total radiation dose, including BT, of 60 Gy (range $44.4{\sim}72$), while 144 patients received a dose higher than 40 Gy. Despite the treatment, the disease recurrence rate was 101/160 (63.1%). Of these, the patterns of recurrence were local in 20 patients (12.5%), persistent disease and local progression in 61 (38.1%), distant metastasis in 15 (9.4%), and concomitant local and distant failure in 5 (3.1%). The overall survival rate was 31.8% at 2 years and 14.2% at 5 years (median 11.1 months). Disease-free survival was 29.0% at 2 years and 22.7% at 5 years (median 10.4 months). The response to treatment and N-stage were significant factors affecting overall survival. In addition, total radiation dose (${\geq}50\;Gy$ vs. < 50 Gy), BT and fractionation scheme (qd. vs. bid.) were not significant factors for overall survival and disease-free survival. Conclusion: Survival outcome after definitive chemoradiation therapy in unresectable esophageal cancer was comparable to those of other series. The main failure pattern was local recurrence. Survival rate did not improve with increased radiation dose over 50 Gy or the use of brachytherapy or hyperfractionation.

• Korean Journal of Clinical Pharmacy
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• v.13 no.1
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• pp.29-39
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• 2003

Neurodegenerative disorders are associated with apoptosis as a causing factor or an inducer. On the other hand, it has been reported that epigallocatechin gallate (EUG), one of antioxidants and flavonoids, and z-VAD-fmk, a nonselective caspase inhibitor, suppress oxidative-radical-stress-induced apoptosis. However, it is not yet known what is the effects of EGCG and z-VAD-fmk on the apoptotic pathway is through phosphoinositide 3-kinase (PI3K), Akt and glycogen synthase kinase-3 (GSK-3) as well as mitochondria, caspase-3 and poly (ADP-ribose) polymerase (PARP). We investigated the effects of EGCG by using $H_2O_2$ treated N18D3 cells, mouse DRG hybrid neurons. Methods: Following 30 min $100\;{\mu}m\;H_2O_2$ exposure, the viability of N18D3 cells (not pretreated vs. EGCG or z-VAD-fmk pretreated) was evaluated by using MTT assay. The effect of EGCG on immunoreactivity (IR) of cytochrome c, caspase-3, PARP, PI3K/Akt and GSK-3 was examined by using Western blot, and was compared with that of z-Y4D-fmk. Results: EGCG or z-VAD-fmk pretreated N18D3 cells showed increased viability. Dose-dependent inhibition of caspase-3 activation accompanied by PARP cleavage were demonstrated by pretreatment of both agents. However, inhibition of cytochrome c release was only detected in EGCG pretreated N18D3 cells. On the pathway through PI3K/Akt and GSK-3, however, the result of Western blot in EGCG pretreated N18D3 cells showed decreased IR of Akt and GSK-3 and increased IR of p85a PI3K, phosphorylated Akt and GSK-3, and contrasted with that in z-VAD-fmk pretreated N18D3 cells showing no changes on each molecule. Conclusion: These data show that EGCG affects apoptotic pathway through upstream signal including PI3K/Akt and GSK-3 pathway as well as downstream signal including cytochrome c and caspase-3 pathway. Therefore, these results suggest that EGCG mediated activation of PI3K/Akt and inhibition GSK-B could be new potential therapeutic strategy for neurodegenerative diseases associated with oxidative injury.

• Journal of KIISE:Software and Applications
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• v.29 no.8
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• pp.584-594
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• 2002

In information retrieval or digital library, one of the most important factors is to find out the exact information which users need. In this paper, we present an efficient index term extraction method which makes it possible to guess the content of documents and get the information more exactly. To find out index terms in a document, we use lexical chains. Before generating lexical chains, we roughly disambiguate the senses of nouns in a document using specific concept, called semantic window. Semantic window is that we look ahead semantic relations of peripheral nouns and disambiguate the senses of nouns. After generating lexical chains with sense-disambiguated nouns, we find out strong chains by some metrics and extract index terms from a few strong chains. We evaluated our system, using results of a key phrase extraction system, KEA. This system works in general domains of documents Including Information Retrieval and Digital Library.

• Journal of IKEEE
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• v.13 no.1
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• pp.57-64
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• 2009

The optoelectrical characteristics of the ZnO nanoparticles (NPs) annealed in vacuum or oxygen condition from $200^{\circ}C$ to $600^{\circ}C$ were examined. Increased on-off ratio (or, the ratio of photocurrent to dark current) was observed when they were annealed at $300^{\circ}C$, $400^{\circ}C$ and $500^{\circ}C$ with the values enhanced about 4 orders compared to the as-prepared ZnO NPs in both annealing conditions, while the maximum efficiency was shown at the annealing temperature of $600^{\circ}C$ for the ZnO NPs annealed in vacuum with the value of 29.8 mA/W and at the temperature of $500^{\circ}C$ for those annealed in oxygen condition with the value of 40.3 mA/W. Photoresponse behavior of the ZnO NPs annealed in oxygen showed the sharp increase right after the ir exposure to the light followed by the slow decay and saturation during steady illumination, differing from the ZnO NPs annealed in vacuum which only exhibited the gradual increase. This difference occurred due to the curing effect of the oxygen vacancies. SEM images indicated no change in their morphologies with annealing, indicating the change in their internal structures by annealing, and most remarkably at $600^{\circ}C$. As for their photoluminescence(PL) spectra, the decrease of the deep-level(DL) emission was observed when they were annealed in oxygen at $400^{\circ}C$, and not at $200^{\circ}C$ and $600^{\circ}C$.