• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.12C
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• pp.1142-1148
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• 2007

In this paper, we propose ASLM (Adaptive Selective Mapping; ASLM) scheme based on peak observation for PAPR (Peak-to-Average Power Ratio) reduction of OFDM (Orthogonal Frequency Division Multiplexing) signals. The proposed scheme is composed of three steps: peak scaling, sequence selection, and SLM procedures. In the first step, the peak signal samples in the IFFT (Inverse Fast Fourier Transform) outputs of the original input sequence are scaled down. In the second step, the sub-carrier positions where the power difference between the original input sequence and the FFT output of the scaled signal is large, are identified. Then, the phase sequences having the maximum number of phase-reversed sequence words only for these positions are selected. Finally, the generic SLM procedure is performed by using only the selected phase sequences for the original input sequence. Simulation results show that the proposed scheme significantly reduces the complexity in terms of IFFT and PAPR calculation than the conventional SLM, while maintaining the PAPR reduction performance.

• Ocean and Polar Research
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• v.28 no.3
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• pp.339-352
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• 2006

Seasonal and tidal variations of density stratification in the Saemangeum waters are investigated based on synoptic CTD observations between July 2003 and September 2005. CTD data used in this study are those obtained after closing the dike No. 4 and before closing the two final gaps, the Sinsi and the Garyeok, on the Saemangeum tidal harrier. A total of 19 field campaigns comprehend a wide temporal spectrum, that is, few seasons, spring and neap tides, and high and low waters. In addition, ADCPs were anchored and CTDs were cast at three stations for 25 h in July 2005. Water columns are vertically homogeneous in autumn and winter. The vertical homogeneity persists in spring but with an occasional weak stratification in i:he northern part of the Gogunsan Islands. Increased reshwater runoff tends to stabilize the water columns and strong density stratification is established in summer. The mean potential energy anomaly (PEA) in summer used as a stratification parameter is the largest $(27.7\;J\;m^{-3})$ in the northern part of the Gogunsan Islands where the Geum River discharge dominates, the smallest $(16.9\;J\;m^{-3})$ is in the inner area of the barrier, in between the two $(21.6\;J\;m^{-3})$ in the southern part of the Gogunsan Islands. Whereas the stratification is generally strengthened in summer, strong winds or large tidal currents over the shallow depths frequently destratify the water column near the mouth of river runoff inside the tidal barrier. Periodic stratification, the development of stratification on the ebb and its breakdown on the flood, occurs in the mid-area inside the barrier induced by the tidal straining, which can also be found in the results of 25 h observation.

• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.18-23
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• 1998

In order to obtain leading compound for the development of new pesticide through the organic synthesis of natural products, the synthesis of ricinine, an active compound of Ricinus communis, was established and biological activities of synthetic compounds against insects were examined. The synthetic scheme of ricinine was composed of four steps by the spontaneous condensation of the cyanoacetyl chloride. A modified synthetic process was also estabilshed to enhance the synthetic yield by simple cyclization of ethoxymethylene malononitrile. In the bioassay results of synthetic ricinine and intermediates on four insects, the mortality of ricinine on brown planthopper (BPH, Nilaparvata lugens) and pea weevil(PW, Bruchus rufimanus) was 80% and 75% at the concentration of 1,000 ${\mu}g/ml$ respectively. Chloronorricinine and chlororicinic acid having chloride group in molecular structure gave 60% mortality on two-spotted mite (TSSM, Tetranychus urticae) at the concentration of 500 ${\mu}g/ml$. The mortality of compounds on house mosquito (HM, Culex pipens pallens) was meager at 10 ${\mu}g/ml$ level.

• Journal of Plant Biotechnology
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• v.29 no.2
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• pp.79-84
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• 2002

Suppression subtractive hybridization (SSH) was used to isolate wound-induced cDNAs from wounded soybean. One of wound-induced cDNA, gmwi33 showed high homology with genes encoding $\beta$-amyrin synthase. The full length cDNA of gmwi33, designated GmAMS1, is 2416 bp long and contains an open reading frame consisted of 739 amino acids. GmAMS1 protein showed 89% identity with licorice GgbAS1 and 86% identity with pea OSCPSY. In 5 day-old, dark-grown seedlings, the expression of GmAMS1 was most strongly induced by light and weakly induced by methyl jasmonate and by low temperature. However, GmAMS1 was not induced by elicitor or UV-B treatment. Such expression pattern might be closely related with the oxygen-radical scavenging activity of soyasaponin.

• Journal of Photoscience
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• v.5 no.1
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• pp.1-10
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• 1998

The susceptibility of chilling-resistant spinach plants. and of chilling-sensitive squash plants to photoinhibition was compared in terms of the activity of photosystem II, in relation to the deuce of fatty acid unsaturation of chloroplast membrane lipids. From thylakoid membranes of the plants. monogalactosyl diacylgtycerol, digalactosyl diacylglycerol. sulfoquinovosyt diacylglycerol, and phosphatidylglycerol were seperated as major lipid classes. It was found that the content of cis-unsaturated fatty acids of phosphatidylglycerol was greater by 32% in spinach than that in squash. When leaf disks were exposed to light at 5$\circ$C, 15$\circ$C and 25$\circ$C, photochemical efficiency of photosystem II. measured as the ratio of the variable to the maximum fluorescence of chlorophyll, declined markedly in squash plants, as compared to spinach plants. When leaf disks were exposed to strong light in the presence of lincomycin, an inhibitor of protein synthesis in chloroplasts, photoinhibition was accelerated in the two types of plants. Moreover, lincomycin treatment abolished the differences in the degree of susceptibility to strong light, which had been observed between the two types of plants. When the extent of photoinhibition of photosystem II-mediated electron transport was compared in thylakoid membranes isolated from the two types of plants, there were no differences in the degree of inactivation of photosystem II activity. However, when intact leaf disks were exposed to strong light either at 10$\circ$C or at 25$\circ$C, and then were allowed to recover either at 17$\circ$C or at 25$\circ$C in dim light. chilling-resistant plants such as spinach and pea showed marked recovery from photoinhibition, in contrast to chilling-sensitive plants, such as squash and sweet potato. whose recovery was strongly dependent on the temperature. These findings are discussed in relation to the unsaturation of fatty acids in membrane phosphatidylglycerol. It appears that fatty acid unsaturation of membrane lipids accelerates the recovery of photosystem H from photoinhibition, without affecting the photo-induced inactivation process of photosystem II associated with photoinhibition.

• Korean Journal of Weed Science
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• v.14 no.1
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• pp.71-80
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• 1994

Nepal, with its unique geographical and ecological features due to its abrupt rise in altitude, plays significant role in biological evolution. Existence of numerous wild relatives of the present-day cultivated agricultural crop plants in this small Himalayan nation may serve as a potential source of several yet unidentified desirable genes that are needed for future incorporation in the improvement of cultivated crop plants. This report includes 82 different wild relatives of 41 genera under 19 families of 37 agricultural crops of Nepal(Table 1). It serves as the sample of the glossary of these wild relatives of crop plants in Nepal. Under food grain crop plants of gramineae, leguminoceae and polygonaceae families, 16 different wild species namely wild rices(7 species), wild relatives of wheat plant(3 species), wild arhar(3 species), wild fingermillets(1 species) and wild buckwheat(2 species) have been identified in different parts of the country. Similarly, under vegetable crop plants of Araceae, Amaranthaceae, Crucifereae, Cucurbitaceae, Dioscoreaceae, Labiteae, Leguminosae, Liliaceae, Malvaceae, Polygonaceae, Solanaceae and Umbellifereae, 37 different wild species-wild colocasia(1 species), wild amaranths(3 species), wild leafy vegetables(2 species), wild gourds(3 species), wild cucumber(1 species), wild yams(4 species), wild mints(3 species), wild fenugreeks(4 species), wild pea(1 species), wild beans(3 species), wild garlics(2 species), wild spinach(3 species), wild lady's finger(1 species), wild spinach(3 species), wild eggplants(2 species) and wild carrot(one species) have also been identified. In case of wild relatives of cultivated orchard plants, 11 different wild species namely wild mango(one species), wild banana(one species), wild strawberry(one species), wild pear(one species), wild cherries(2 species), wild apple(one species) and wild grapes(3 species) have been identified, Among 19 different wild species of economic crop plants, five wild species of sugarcane, one species of wild sunhemp, two wild relatives of cotton, three wild relatives of rose, two wild species of tobacco, four wild species of turmeric and two wild species of tea have also been identified. This report includes only sample of the total wild species of the present-day cultivated agricultural crop plants. Further exploration on this economic botany will help the country in cataloging the wild relatives of cultivated crop plants and their future use in crop improvement.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.546-550
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• 1997

This study was carried out to elucidate the biological characteristics of Rhizobia in biological nitrogen fixation system. The results of investigation were as follows; Polyacrylamide gel electrophoresis pattern of root lectin in the presence of SDS was ascertained electrophoretically and chromatographically. The purified root lectin formed immunoprecipitin line with anti lectin rabbit IgG. Root lectin, seed lectin and root exudate were tested for chemotactic ability. Chemotactic responses of RCR3407 and KCTC2422 toward root exudate were stronger than those of seed lectin and root lectin, but there didn't occur chemotactic responses of LPN100, not bound with seed lectin and that of LPN101, bound with seed lectin toward root exudate, root lectin and seed lectin. RCR3407, KCTC2422 and LPN-101, which nodulated with soybean, interacted with soybean lectin, but not with pea lectin. LPN-100, which was not nodulated with soybean, didn't interact with soybean lectin.

• The Korean Journal of Food And Nutrition
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• v.31 no.1
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• pp.43-51
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• 2018

This study was conducted to investigate the quality of pumpkin paste added with different starches during storage at $4^{\circ}C$ for 8 days. Pumpkin paste was evaluated for pH, carotenoid, syneresis, color values, texture, and sensory characteristics. The properties of the pumpkin paste were studied on three different starches (CON: control, MCP: cow pea starch, MMB: mung bean starch, and MSP: sweet potato starch). The initial pH of the pumpkin paste with starches were 6.13~6.16. The pH of pumpkin paste increased as the starches added increased. The carotenoid content of CON was higher in the pumpkin paste processing. The change of syneresis significantly increased with the storage period, and the amount of change of MCP and MMB added with starch was smaller than CON without the added starch. The Hunter's L-values of the pumpkin paste increased, whereas the a- and b-value decreased as the amount of starches added increased. The results of the textural analysis showed that the hardness of MCP and MMB was different from that of other pumpkin paste, showing a lower value such as 38.26 g, 38.93 g, while CON and MSP was 40.43 g and 42.49 g, respectively. A sensory evaluation indicated that starches could enhance the overall texture characteristics of pumpkin paste. In terms of the overall acceptance of the pumpkin paste, the experimental group with MCP scored the best.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.07a
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• pp.57-62
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• 1999

Light-regulated translation of chloroplast mRNAs requires nuclear-encoded trans-acting factors that interact with the 5' untranslated region (UTR) of these mRNAs. A set of four proteins (60, 55, 47, and 38 kDa) that bind to the 5'-UTR of the psbA mRNA had been identified in C. reinhardtii. 47 kDa protein (RB47) was found to encode a chloroplast poly (A)-binding protein (cPABP) that specifically binds to the 5'-UTR of the psbA mRNA, and essential for translation of this mRNA, cDNA encoding 60 kDa protein (RB60) was isolated, and the amino acid sequence of the encoded protein was highly homologous to plants and mammalian protein disulfide isomerases (PDI), normally found in the endoplasmic reticulum (ER). Immunoblot analysis of C. reinhardtii proteins showed that anti-PDI recognized a distinct protein of 56 kDa in whole cell extract, whereas anti-rRB60 detected a 60 kDa protein. The ER-PDI was not retained on heparin-agarose resin whereas RB60 was retained. In vitro translation products of the RB60 cDNA can be transported into C. reinhardtii chloroplast in vitro. Immunoblot analysis of isolated pea chloroplasts indicated that higher plant also possess a RB60 homolog. In vitro RNA-binding studies showed that RB60 modulates the binding of cPABP to the 5'-UTR of the psbA mRNA by reversibly changing the redox status of cPABP using redox potential or ADP-dependent phosphorylation. Site-directed mutagenesis of -CGHC- catalytic site in thioredoxin-like domain of RB60 is an unique PDI located in the chloroplast of C. reinhardtii, and suggest that the chloroplast PDI may have evolved to utilize the redox-regulated thioredoxin like domain as a mechanism for regulating the light-activated translation of the psbA mRNA.

• Proceedings of the Botanical Society of Korea Conference
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• 1998.07a
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• pp.10-18
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• 1998

For improvement of plants in disease resistance, it is most important to elucidate the mechanism to perceive and respond to the signal molecules of invaders. A model system with pea and its pathogen, Mycosphaerella pinodes, showed that the fungal elicitor induced defense responses in all plant species tested but that the suppressor of the fungus blocked or delayed the expression of defense responses and induced accessibility only in the host plant. In the world, many researchers believe that the pathogens` signals are recognized only on the receptors in the plasma membranes. Though we found that the ATPase and polyphosphoinositide metabolism in isolated plasma membranes responded to these fungal signals, we failed to detect specific actions of the suppressor in vitro on these plasma membrane functions. Recently, we found that ATPase (NTPases) and superoxide generating system in isolated cell wall were regulated by these fungal signals even in vitro, especially, by the suppressor in a strictly species-specific manner and also that the cell wall alone prepared an original defense system. The effects of both fungal signals on the isolated cell wall functions in vitro coincide perfectly with those on defense responses in vivo. In this treatise, we discuss the key role of the cell wall, which is plant-specific and the most exterior organelle, in determining host-parasite specificity and molecular target for improvement of plants.