• Journal of The Korean Astronomical Society
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• v.37 no.4
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• pp.199-203
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• 2004

The gas response to a proposed spiral stellar pattern for our Galaxy is presented here as calculated via 2D hydrodynamic calculations utilizing the ZEUS code in the disk plane. The locus is that found by Drimmel (2000) from emission profiles in the K band and at 240 ${\mu}m$. The self-consistency of the stellar spiral pattern was studied in previous work (see Martos et al. 2004). It is a sensitive function of the pattern rotation speed, $\Omega$p, among other parameters which include the mass in the spiral and its pitch angle. Here we further discuss the complex gaseous response found there for plausible values of $\Omega$p in our Galaxy, and argue that its value must be close to $20 km s^{-l}\;kpc^{-1}$ from the strong self-consistency criterion and other recent, independent studies which depend on such parameter. However, other values of $\Omega$p that have been used in the literature are explored to study the gas response to the stellar (K band) 2-armed pattern. For our best fit values, the gaseous response to the 2-armed pattern displayed in the K band is a four-armed pattern with complex features in the interarm regions. This response resembles the optical arms observed in the Milky Way and other galaxies with the smooth underlying two-armed pattern of the old stellar disk populations in our interpretation. The complex gaseous response appears to be related to resonances in stellar orbits. Among them, the 4:1 resonance is paramount for the axisymmetric Galactic model employed, and the set of parameters explored. In the regime seemingly proper to our Galaxy, the spiral forcing appears to be marginally strong in the sense that the 4:1 resonance terminates the stellar pattern, despite its relatively low amplitude. In current work underway, the response for low values of $\Omega$p tends to remove most of the rich structure found for the optimal self-consistent model and the gaseous pattern is ring-like. For higher values than the optimal, more features and a multi-arm structure appears.

• Macromolecular Research
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• v.11 no.4
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• pp.207-223
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• 2003

For last five years, we are developing the novel local drug delivery devices using biodegradable polymers, especially polylactide (PLA) and poly(D,L-lactide-co-glycolide) (PLGA) due to its relatively good biocompatibility, easily controlled biodegradability, good processability and only FDA approved synthetic degradable polymers. The relationship between various kinds of drug [water soluble small molecule drugs: gentamicin sulfate (GS), fentanyl citrate (FC), BCNU, azidothymidine (AZT), pamidronate (ADP), $1,25(OH)_2$ vitamin $D_3$, water insoluble small molecule drugs: fentanyl, ipriflavone (IP) and nifedipine, and water soluble large peptide molecule drug: nerve growth factor (NGF), and Japanese encephalitis virus (JEV)], different types of geometrical devices [microspheres (MSs), microcapsule, nanoparticle, wafers, pellet, beads, multiple-layered beads, implants, fiber, scaffolds, and films], and pharmacological activity are proposed and discussed for the application of pharmaceutics and tissue engineering. Also, local drug delivery devices proposed in this work are introduced in view of preparation method, drug release behavior, biocompatibility, pharmacological effect, and animal studies. In conclusion, we can control the drug release profiles varying with the preparation, formulation and geometrical parameters. Moreover, any types of drug were successfully applicable to achieve linear sustained release from short period ($1{\sim}3$ days) to long period (over 2 months). It is very important to design a suitable formulation for the wanting period of bioactive molecules loaded in biodegradable polymers for the local delivery of drug. The drug release is affected by many factors such as hydrophilicity of drug, electric charge of drug, drug loading amount, polymer molecular weight, the monomer composition, the size of implants, the applied fabrication techniques, and so on. It is well known that the commercialization of new drug needs a lot of cost of money (average: over 10 million US dollar per one drug) and time (average: above 9 years) whereas the development of DDS and high effective generic drug might be need relatively low investment with a short time period. Also, one core technology of DDS can be applicable to many drugs for the market needs. From these reasons, the DDS research on potent generic drugs might be suitable for less risk and high return.

• Journal of Life Science
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• v.25 no.2
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• pp.121-129
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• 2015

Alginates are found in marine brown seaweeds and in extracellular biofilms secreted by some bacteria. Previously, we reported an oligoalginate lyase from Sphingomonas sp. MJ-3 (MJ3-Oal) that had an exolytic activity and protein sequence homology with endolytic polymannuronate (polyM) lyase in the N-terminal region. In this study, the MJ3-Oal was tested for both exolytic and endolytic activity by homology modeling using the crystal structure of Alg17c from Saccharophagus degradans 2-40T. The tyrosine residue at the $426^{th}$ position, which possibly formed a hydrogen bond with the substrate, was mutated to phenylalanine. The FPLC profiles showed that MJ3-Oal degraded alginate quickly to monomers as a final product through the oligmers, whereas the Tyr426Phe mutant showed only exolytic alginate lyase activity. $^1H$-NMR spectra also showed that MJ3-Oal degraded the endoglycosidic bond of polyM and polyMG (polymannuronate-guluronate) blocks. These results indicate that oligoalginate lyase from Sphingomonas sp. MJ-3 probably catalyzes the degradation of both exo- and endo-glycosidic bonds of alginate.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.133-141
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• 2012

This study was carried out to investigate the effects of substitution of fermented king oyster mushroom (P. eryngii) by-products diet on pork meat quality characteristics, during the storage. A mixture of 40% king oyster mushroom by-products, 28% soybean meal and 20% corn was fermented for 10 d, and the basal diet was then substituted by the fermented diet mixture of up to 20, 50 and 80%, respectively. A total of 96 pigs were fed experimental diet (8 pigs per pen ${\times}$ 4 diets ${\times}$ 3 replication), and eight longissiumus (LD) per treatment were collected, when each swine reached to 110 kg of body weight. The Warner-Bratzler shear forces and cooking loss were significantly lowered in the treatments, while crude protein content and water holding capacity significantly (p<0.05) increased in the treatments than in the control group. The volatile basic nitrogen (VBN), at 1 d of storage, was lower in the treatments, while texture profiles and sensory evaluation did not differ between the control and the treatments (p>0.05). The pH, thiobarbituric acid reactive substances (TBARS), VBN and meat color in all treatments were increased as storage increased. Fermented king oyster mushroom by-products diet effects on lightness (CIE $L^*$), yellowness (CIE $b^*$) and chroma were determined, when LD muscles in T2 and T3 treatments were higher (p<0.05), up to 7 d (p<0.05). Therefore, the results indicate that the substitution of the fermented king oyster mushroom by-products diet to swine diet influenced the quality of the meat and it may be an economically valuable ingredient.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1817-1826
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• 2014

This study investigated lipid profiles and antioxidant capacities of seven Korean rapeseed cultivars (Naehan, Tamla, Mokpo111, Yeongsan, Tammi, Hanla, and Mokpo68). The rapeseeds contained 29.3~33.2% of extracted lipid and major fatty acids were oleic, linoleic, and linolenic acids. The ratio of omega-6/omega-3 fatty acids was 2.20~3.68 with the highest in Hanla and lowest in Naehan. Glycolipid ranged from 0.21 g/100 g to 0.47 g/100 g. Phospholipid content was 0.55~1.15 g/100 g with the highest in Tammi and the lowest in Mokpo68, and the most common phospholipid was phosphatidylcholine. Tocopherol content was 9.45~15.11 mg/100 g in the order of ${\gamma}$ > ${\alpha}$ > ${\beta}$ > ${\delta}$-tocopherol, and Naehan contained the highest amount of tocopherols (P<0.05). Total phenol content (TPC) of rapeseed was 314.64~577.08 mg SAE/100 g. Tamla contained the highest TPC, and showed the highest antioxidant activity determined by 1,1-diphenyl-2-picrylhydrazyl free radical scavenging capacity and ferric reducing antioxidant power.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1052-1058
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• 2005

Structured lipid (SL) was synthesized by enzymatic interesterification with algae oil containing docosahexaenoic acid (DHA) and soybean oil in the stirred-batch type reactor. The reaction was performed for 15hr at $65^{\circ}C$ with 300 rpm catalyzed by sn-1,3 specific Lipozyme RM 1M lipase from Rhizomucor miehei ($11\%$ by weight of total substrates) in the absent organic solvent. SL contained $87.1\;area\%$ triacylglycerol (TAG), $12.1\;area\%$ diacylglycerol (DAG), $0.6\;area\%$ monoacylglycerol (MAG), and $0.2\;area\%$ free fatty acid (FFA). Major fatty acid profiles of SL were DHA $(15.7\;mol\%)$, linoleic $(31.1\;mol\%)$, palmitic $(20.2\;mol\%)$, oleic $(13.5\;mol\%)$ and eicosapentaenoic acid $(EPA,\;6.6 mol\%)$. SL contained the newly synthesized several peaks. Iodine and saponification of SL were 206.7 and 183.8. SL color showed darker and redder than soybean oil, and appeared the most yellowish color among SL, soybean, and algae oil.

• Korean Journal of Agricultural Science
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• v.44 no.3
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• pp.409-415
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• 2017

This study was conducted to investigate the effect of supplementation of fermented wheat bran (FWB) on growth and blood characteristics in weaned pig. A total of 36 weaned pigs ($Landrace{\times}Yorkshire{\times}Duroc$; BW, $7.78{\pm}0.04kg$) were randomly allocated to three dietary treatments with different FWB concentrations (0, 0.5, and 1.0%), and each treatment had 3 replicate pens with 4 pigs per pen. The FWB was obtained from a mixture of wheat bran and two microbes (Lactobacillus plantarum M10 and Saccaromyces cerevisiae) and was determined to contain $10.19{\pm}0.27log\;CFU/g$ of L. plantarum and $7.73{\pm}0.38log\;CFU/g$ of S. cerevisiae. Experimental diets were prepared by mixing 0 (control), 0.5, or 1.0% of the FWB to the basal diet, and fed to the weaned pigs for 7 weeks. During the experimental period, the pigs had access to the diet and water ad libitum. Feed intake increased significantly in the 1.0% FWB group compared to the control and 0.5% FWB groups (p < 0.05), whereas the other growth parameters were not different among the treatment groups. White blood cells and lymphocytes were significantly decreased in the FWB treatment groups compared to the control group, but other blood corpuscles were not different among the treatment groups (p < 0.05). The pigs fed 0.5% FWB showed greater serum IgG than the control and 1.0% FWB groups (p < 0.05). In conclusion, the FWB fed to weaned pigs did not negatively affect their growth performance, but rather reduced mortality by fortifying immunity.

• Progress in Medical Physics
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• v.7 no.1
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• pp.53-64
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• 1996

Purpose: The purposes of this paper are to develop a theoretical basis that the beam directions should be considered when the mechanical accuracy of teletherapy machine is evaluated by the star pattern test, to develop methods using asymmetric field in length to simulate beam direction for the case that beam direction does not appear on film. Method: In evaluating mechanical rotational accuracy of the gantry of teletherapy unit by the star pattern test, the direction of radiation beams was considered. A star pattern using some narrow beams was made. Density profiles at 10cm far from estimated gantry axis on the star pattern were measured using an optical densitometer. On each profile, one coordimate of a beam axis was determined. A pair of coordinates on a beam axis form an equation of the axis. Assume that a unit vector equation omitted is with same direction as radiation beam and a vector equation omitted is a vector directing to the beam axis from the estimated gantry axis. Then, a vector product equation omitted ${\times}$ equation omitted is an area vector of which the absolute value is equal to the distance from the estimated gantry axis to the beam axis. The coordinate of gantry axis was obtained by using least-square method for the area vectors relative to the average of whole area vectors. For the axis, the maximum of absolute value of area vectors would be an accuracy of the gantry rotation axis. For the evaluation of mechanical accuracies of collimator and couch axes for which beam direction could not be depicted on a star pattern test film, narrow beams asymmetric in field length was used to simulate beam direction. Result: For a star test pattern to evaluate the mechanical accuracy of rotational axes of a telectherapy machine, the result considering beam direction was different from that ignoring beam direction. For the evaluation of mechanical accuracies of collimator and couch axes by means of a star pattern test, narrow asymmetric beams could simulate beam direction. Conclusion: When a star pattern test is used to evaluate the mechanical accuracy of a teletherapy unit, beam direction must be considered or simulated, and quantitatively evaluated.

• The Korean Journal of Zoology
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• v.31 no.3
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• pp.236-242
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• 1988

Mitochondrial DNAs of two Mdh allelotypes of the dark chub, Z. temmincki inhabiting in Korean fresh water, were analysed. Samples of each type were collected from four populations, and the fragment patterns for mtdNA of each type were explained from 7 of the eleven restriction enzymes with hexanucleotide recognition site. Genome size was approximately 16.7 kilobases. The highly typical mtdNA fragments of each type were discovered in digestion profiles produced by Eco RI and Pst I enzyrnes. The comparisons of restriction fragment patterns and relative digestion maps permitted the estimation of fragment homology (F) and nucleotide sequence divergence(p). Between the two identical types, sequence divergence(p) was 0.128(MS), and 0.045(MM), ; between the two different types, 0.195 (range 0.177-0.226). These result may provide a distinct difference more than the value derived from allozyrne analysis, and a powerful new molecular approach for assessing genetic-evolutionary relationship among fishes.

• Food Science and Preservation
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• v.23 no.7
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• pp.953-959
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• 2016

The quality characteristics and processing of rice cake (Backsulgi) with rice flour containing Lactobacillus plantarum CGKW3 by spray-drying (LP-B) were investigated. The LP-B was applied at ratios of 10, 20, and 30 (w/w), and the moisture contents and pH were 33.39%~36.70% and 5.81~5.46, respectively. The L value of LP-B increased as the rice flour decreased, while the a and b value increased as the LP-B increased. The texture profiles showed that Backsulgi prepared with LP-B mixture had higher hardness, cohesiveness, springiness and chewiness than 100% rice flour. The pH of LP-B Backsulgi (LP-B20 and LP-B30) did not differ during 6 days at room temperature. The total bacteria in Backsulgi prepared LP-B20 and LP-B30 Backsulgi was $10^4CFU/g$ after 2 days of storage at room temperature. The shelf life of Backsulgi prepared with LP-B20 and LP-B30 were extended by about 2 days when compared with the control at room temperature. Sensory evaluation showed that Backsulgi without LP-B20 had higher scores in terms of appearance, color, flavor, taste, texture, hardness and overall acceptability than Backsulgi without 100% rice flour. In conclusion, the results demonstrate that LP-B20 may prove quite useful as a Backsulgi flour with desirable properties.