• Journal of Industrial Technology
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• v.18
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• pp.259-265
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• 1998

The molecular weights of surfactant SDS(M.W. 288) and SLS(M.W. 420) are smaller than the molecular weigh cut-off of cellulose acetate membrane used in this study. However, 20% of SDS and 67% of SLS were rejected by cellulose aectate membrane. The higher rejection rate of SLS than that of SDS is due to the longer hydrophobic chain and greater molecular weight. There was no resistance to permeation rate by membrane fouling. Most of permeation resistance was due to the concentration polarization. Permeation rate was declined with operating time and with increase in concentration of surfactant due to concentration polarization.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.430-433
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• 1996

The activity of PAL, an initial and key regulatory enzyme in biosynthesis of phenolics, peaked during ripening stage. The enzyme activities were 5.60 and 4.25 units/100g fr. wt. in ripening and overripening stages. The increase in PAL activity in ripening strawberry fruits is due to de novo synthesis of the enzyme. PAL extracts from ripe strawberry fruits have a native molecular weight of about 260, 000 Da.

• Korean Journal of Human Ecology
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• v.1 no.2
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• pp.119-128
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• 1998

Nonwoven fabrics for diaper coverstock were treated with chitosan solution by pad-dry method. Two chitosans of different molecular weigh(Mw) with similar degree of deacetylation(DDA) were used: Mw 1,800(chitosan oligomer, DDA 84%). Effect of chitosan treatment on the mechanical properties was investigated using KES-FB system. Primary hand values were calculated from mechanical properties using the same equation as the men's suiting equation with minor modification, and total hand values were calculated using new KN-5LNW equation for nonwoven fabrics developed by Kawabata et al. Increase in chitosan treatment concentration increased B, 2HB, WT, LT and RC, and decreased WC continuously. Chitosan treatment affected other mechanical properties regardless of molecular weight. Considering primary hand values obtained from mechanical properties, it was found that chitosan of Mw 180,000 and chitosan oligomer provided softer, smoother, and more bulky at below 0.05% and above 0.5% treatment concentration respectively. Samples treated with 1.0% chitosan oligomer solution, and 0.01％ chitosan solution of Mw 180,000 showed the best total hand values. (Korean J Human Ecology 1(2):119∼128, 1998)

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.4005-4010
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• 2011

We investigated thermal behavior of spin-coated films of P(HB-co-HHx)/PEG blends by using infraredreflection absorption (IRRAS) spectroscopy and 2D correlation spectroscopy. Based on 2D IRRAS correlation spectra, we could determine the sequence of spectral intensity changes with increasing temperature that PEG band changes first and then a band for crystalline component of P(HB-co-HHx) changes before a band for amorphous component. The intensities of bands for PEG and amorphous P(HB-co-HHx) were changed greatly as PEG weigh % of P(HB-co-HHx)/PEG blends increased. Transition temperatures of P(HB-co-HHx)/PEG blends were successfully determined by 2D gradient mapping method. The transition temperature of spincoated films of 98/2 and 90/10 P(HB-co-HHx)/PEG blends and 80/20 P(HB-co-HHx)/PEG blend determined by 2D gradient map are, respectively, about 137.5 and $132.5^{\circ}C$. Furthermore, P(HB-co-HHx)/PEG blends show an additional transition temperature that have been interpreted in terms of different lamellar thicknesses in spin coated films.

• Korean Journal of Microbiology
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• v.27 no.1
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• pp.35-42
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• 1989

The mode of transglycosylation reaction observed during the action of low-molecular-weigh $\beta$-D-glucosidase ($\beta$-D-glucoside glucohydrolase, EC3.2.1.21) purified from Trichoderma koningii ATCC 26113 was investigated using $^{1}H$-NMR spectroscopy. The enzyme was purified by the series of procedures including ammonium sulfate precipitation, and fractionations by column chromatographies on Bio-Gel P-150, DEAE-Sephadex A-50, and SP-Sephadex C-50. The final purification was performed by the band eluation after preparative polyacrylamide gel electrophoresis. The enzyme showed its molecular size of 78,000 through the analysis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis and its isoelectric point of 5.80 through the analysis of analytical isoelectric focusing. The H-1 proton resonances were analyzed. After the reaction of the enzyme with cellobiose, the reaction products were separated by high performance liquid chromatography using refractive index detector. H-1 resonances of the products were consisted with those of gentiobiose [$\beta$-D-glucopyranosyl--(1,6)-D-glucopyranose], and cellotriose [$\beta$-D glucopyranosyl-(1,4)-$\beta$-D-glucopyranosyl]-(1,4)-D-glucopyranose] with minor resonances of sophorose [$\beta$-D-glucopyranosyl-(1,2)-D-glucopyranose], respectively.

• Elastomers and Composites
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• v.25 no.3
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• pp.195-202
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• 1990

Rubber-modified polyurethane resin which was prepolymer type terminated with NCO, was synthesized by reacting isocyanate groups[NCO] and hydroxyl groups[OH]. Polybutadiene rubbers which had OH groups in the side of rubber chains, were charged at ratio $0%{\sim}40%$ of solid component in reactants. For products, physical properties were investigated experimentally. The results abtained in experiment were as follows. 1. Liquid resin and dried film was good solubility and clearity at less than 25%, 20% of rubber without being related to sort. 2. G-1000 showed better properties than R-45HT in solubility, dring time and adhesive strength. 3. Dring time and adhesive strength were considerably influenced by molecular weigh and structure of rubber. 4. In using 25% of mixed rubber(G-1000/R-45HT=50/50), It represented best properties in dring time(10 minute) and adhesive strength($23Kg/cm^2$).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.5
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• pp.346-355
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• 2005

To investigate the application of biochemical markers' and small-sample methods using whole-wheat flours for screening in early generation in Korean wheat breeding system, 74 Korean wheats, including cultivars, local breeding lines and experimental lines, were analyzed. Seed storage protein and amylose contents of grains were evaluated. Biochemical makers, including granule bound starch synthase (GBSS), high molecular weigh glutenin subunits (HMW-GS) and friabilin were also evaluated by using one-dimensional sodium dodecyl sulfate-polyacryla-mide gel electrophoresis with a single kernel. The small­sample methods, including modified SDS-sedimentation test (MST), micro-alkaline water retention capacity (AWRC) and whole-wheat flour swelling volume (WSV) were also tested in this study. Protein content, MST and AWRC was $11.0 - 15.8\%$, 2.7 - 26.2 ml and $71.9 - 109.7\%$, respectively. Apparent and total amylose content and WSV was $20.6 - 25.0\%$, $26.1 - 32.4\%$ and 9.0 - 16.9 ml, respectively. There were highly significant correlations between MST and AWRC (r=0.592, P<0.001), but Korean wheats showed no significant difference in protein content, amylose content and small-sample methods. In the biochemical markers, Korean wheats contained all three GBSS encoded by Wx loci, except for Suwon 252. Korean wheats showed the high frequency ($58.1\%$) of 1Dx2.2 + 1Dy12 subunits of HMW-GS. Friabilin band was present in 46 lines ($62.2\%$) and absent in 28 lines ($37.8\%$). Friabilin-absence lines showed the higher MST (14.9 ml) and AWRC ($92.1\%$) value than friabilin-presence lines (8.5 ml and $82.4\%$, respectively).

• Preventive Nutrition and Food Science
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• v.11 no.3
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• pp.243-252
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• 2006

White salted noodles and pan bread were prepared from Korean wheats with 1Dx2.2+1Dy12 subunits in high molecular weight glutenin subunits (HMW-GS) to evaluate the suitability for end-use products through the comparison with US wheats with various classes and commercial wheat flours. Korean wheat flours with 1Dx2.2+1Dy12 subunits showed higher SDS sedimentation volume than US wheat flours with similar protein content. Compared to wheat flours with similar protein content and SDS sedimentation volume, water absorption percent of Korean wheat flours using a mixograph was higher than that of US wheat flours, but similar to commercial wheat flours. Mixograph mixing time was similar to hard wheat flours and commercial noodle flours. Optimum water absorption percent of noodle dough from Korean wheat flours was higher than that of US wheat flours. Noodle sheets from Korean wheat flours with 1Dx2.2+ 1Dy12 subunits showed lower L values, higher a values and similar b values compared to commercial noodle flours. Hardness of cooked noodles from Korean wheat flours 1Dx2.2+1Dy12 subunits correlated positively with protein content, NIRS hardness, mixograph water absorption and gluten yield of flours. Korean wheat flours with 1Dx2.2+1Dy12 subunits showed lower loaf volume and harder crumb firmness than hard wheat flours and commercial bread wheat flours in spite of similar protein quantity and quality to hard wheat flours.

• Journal of Photoscience
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• v.9 no.2
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• pp.436-438
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• 2002

Since solar radiation contains wavelength essential for photosynthesis accompanying with near-UV light, UV-B effects on biological parameters and acclimation mechanisms are influenced by photosynthetically active radiation (PAR). Therefore, to elucidate near-UV shielding mechanism in higher plants, we cultivated cauliflower under usual solar radiation and increased UV-B from fluorescent lamps, two- or three-fold excess over continuously estimated UV-B dose in PAR during daytime, using computer regulated systems. Increased UV-B radiation had little effect on growth expressed as fresh weigh and leaf area. Water soluble low molecular weight compounds showing absorption in near UV region were enhanced according to the irradiated UV-B dose. One of compounds in cauliflower leaves was identified as chlorogenic acid. This was found to have no near-UV photosenSitizerable activity and is known to have an ability to scavenge a wide species of active oxygen. Another pro-oxidant compound that generates superoxide anion radical under near-UV irradiation was not induced by increased UV-B during cultivation, and identified as lumazine, a degradation product from folic acid.

• BMB Reports
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• v.46 no.1
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• pp.41-46
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• 2013

Identifying genes indispensable for an organism's life and their characteristics is one of the central questions in current biological research, and hence it would be helpful to develop computational approaches towards the prediction of essential genes. The performance of a predictor is usually measured by the area under the receiver operating characteristic curve (AUC). We propose a novel method by implementing genetic algorithms to maximize the partial AUC that is restricted to a specific interval of lower false positive rate (FPR), the region relevant to follow-up experimental validation. Our predictor uses various features based on sequence information, protein-protein interaction network topology, and gene expression profiles. A feature selection wrapper was developed to alleviate the over-fitting problem and to weigh each feature's relevance to prediction. We evaluated our method using the proteome of budding yeast. Our implementation of genetic algorithms maximizing the partial AUC below 0.05 or 0.10 of FPR outperformed other popular classification methods.