• Journal of Biomedical Engineering Research
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• v.25 no.1
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• pp.33-41
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• 2004

Accuracy of registration between images acquired from various medical image modalities is one of the critical issues in radiation treatment planing. In this study, a method of accuracy evaluation of image registration using a homemade brain phantom was investigated. Chamfer matching of CT-MR and CT-SPECT imaging was applied for the multimodal image registration. The accuracy of image correlation was evaluated by comparing the center points of the inserted targets of the phantom. The three dimensional root-mean-square translation deviations of the CT-MR and CT-SPECT registration were 2.1${\pm}$0.8 mm and 2.8${\pm}$1.4 mm, respectively. The rotational errors were ＜ 2$^{\circ}$ for the three orthogonal axes. These errors were within a reasonable margin compared with the previous phantom studies. A visual inspection of the superimposed CT-MR and CT- SPECT images also showed good matching results.

• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.385-390
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• 2010

Bacillus licheniformis fermenting soybean product with highest score in consumer acceptance had been isolated from homemade Cheongkookjang. In order to develop the medium composition, effects of ingredients including nitrogen sources, carbon sources, metal ions and phosphate were examined for protease production of the isolate. Potato starch increased the protease productivity, while glucose repressed it. Yeast extract was the most effective nitrogen source for enzyme production. The calcium was found to increase protease activity slightly while cell growth and enzyme production was completely inhibited by divalent ions such as $Zn^{2+}$, $Cu^{2+}$ and $Co^{2+}$. The maximum protease productivity was reached approximately 800 unit/mL in the optimized medium consisting of potato starch (1.5%), yeast extract (1.5%), $CaCl_2$(0.7%), $K_2HPO_4$(0.03%) and $KH_2PO_4$(0.03%). The protease activity of culture filtrate was gradually decreased after incubation for 28 h.

• Microbiology and Biotechnology Letters
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• v.42 no.4
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• pp.339-346
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• 2014

A bacterial strain was isolated from homemade doenjang (Korean fermented soybean paste) as a producer of the extracellular ${\beta}$-galactosidase, capable of hydrolyzing lactose to liberate galactose and glucose residues. The isolate YB-1414 has been identified as Bacillus licheniformis on the basis of its 16S rDNA sequence, morphology and biochemical properties. The production of ${\beta}$-galactosidase by B. licheniformis YB-1414 reached maximum levels of 6.2 U/ml in culture medium containing wheat bran (1%) and yeast extract (2.5%) as carbon and nitrogen sources, respectively. Particularly, the insoluble fraction was more effective for ${\beta}$-galactosidase production than the soluble extract of wheat bran. The enzyme exhibited maximum activity for hydrolysis of para-nitrophenyl-${\beta}$-D-galactopyranoside (pNP-${\beta}Gal$) under reaction conditions of pH 6.0 and $55-60^{\circ}C$. Its hydrolyzing activity for pNP-${\beta}Gal$ was drastically decreased by the addition of low concentrations of galactose, but only slightly decreased by glucose, with 85% of maximal activity in the presence of 400 mM glucose.

• Journal of the Korean Chemical Society
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• v.36 no.3
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• pp.419-427
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• 1992

The performance of homemade thermal field-flow fractionation (ThFFF) and the optimization for separation are investigated in terms of retention parameters and selectivity using polystyrene standards. The ribbonlike channel was constructed by sandwiching two Mylar spacers between two highly polished copper bars which serve as channel walls. The hot bar was heated by two electrical cartridge heaters and the cold bar had holes through the entire length, allowing tap water as coolant to enter. It has been observed that the retention of polystyrenes increases as the temperature gradient increases. And the retention decreases as the cold wall temperature increases from 20 to $45^{\circ}C$. In comparison with size exclusion chromatography, ThFFF is more selective but has relatively low efficiency. It has been found that the plate height is proportional to the flow velocity and good estimates of polydispersities can be made directly from the ThFFF data.

• Microbiology and Biotechnology Letters
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• v.40 no.1
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• pp.17-22
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• 2012

A bacterial strain was isolated from homemade Cheongkookjang as a producer of the ${\beta}$-galactosidase, capable of hydrolyzing lactose to liberate galactose and glucose residues. The isolate YB-1105 has been identified as Bacillus licheniformis on the basis of its 16S rDNA sequence, morphology and biochemical properties. ${\beta}$-Galactosidase activity was detected in both the culture supernatant and the cell extract of B. licheniformis YB-1105. The enzymes of both fractions demonstrated maximum activity for hydrolysis of para-nitrophenyl-${\beta}$-D-galactopyranoside (pNP-${\beta}Gal$) under identical reaction conditions of pH 6.5 and $50^{\circ}C$. However, ${\beta}$-galactosidase activity from the culture filtrate was affected more than that from the cell free extract at acidic pHs and high temperatures. The hydrolyzing activity of both ${\beta}$-galactosidases for pNP-${\beta}Gal$ was dramatically decreased by the addition of low concentrations of galactose, but was only marginally decreased by high concentrations of glucose or mannose.

• Microbiology and Biotechnology Letters
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• v.42 no.2
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• pp.99-105
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• 2014

A Bacillus strain capable of hydrolyzing locust bean gum was isolated as a producer of extracellular mannanase by way of an enrichment culture in an acidic medium from homemade soybean pastes. The isolate YB-1401 showed a biochemical identity of 61.1% with Brevibacillus laterosporus, while the nucleotide sequence of its 16S rDNA had the highest similarity with that of Bacillus amyloliquefaciens. The mannanase productivity of the Bacillus sp. YB-1401 was drastically increased by mannans. Particularly, maximum mannanase productivity was reached at approximately 265 U/ml in LB medium supplemented with konjac glucomannan (4.0%). The mannanase was the most active at $55^{\circ}C$ and pH 5.5. Mannanase activity was completely maintained after pre-incubation at pH 3.5 to 11.0 for 1 h. The predominant products resulting from the mannanase hydrolysis were mannobiose and mannotriose for LBG, guar gum or mannooligosaccharides. A small amount of mannose was also detected in the hydrolyzates.

• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.705-718
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• 2014

This study was performed to evaluate the suppressive effects of organic fungicides made using environment-friendly materials on leaf spot disease and anthracnose that infect ginseng. Anthracnose (Colletotrichum gloeosporioides) and leaf spot disease (Alternaria panax) are principal diseases that decrease the yield of ginseng by defoliation before root enlargement. Fermented eggs and oyster shells, water extract of green tea and ethanol extract of red ginseng dregs were significantly effective in suppressing leaf spot disease. Fermented crab and shrimp shells and fermented motherwort were also effective in suppressing the recurrence of ginseng anthracnose. The preventive effects of these environment-friendly materials were definitely superior to the therapeutic effects. Therefore, these materials could be used as alternatives to chemical pesticides, which can not be applied in organic ginseng cultivation field. These organic fungicides need to be applied before the incidence of ginseng anthracnose in order to maximize their suppressive effects.

• New Physics: Sae Mulli
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• v.68 no.12
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• pp.1374-1377
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• 2018

We achieved 95% visibility in the Hong-Ou-Mandel interference experiment while we achieved only 56% visibility in a previous report. We used a 120 mW 405 nm single-mode continuous wave laser, a 5-mm-thick type-1 ${\beta}$-barium borate single crystal, standard Hong-Ou-Mandel interferometer optics, two avalanche photodiode single-photon counters, and a homemade coincidence counting unit. The photon collection unit was the key difference between the present study and the previous study. In the present experiment, we used single-mode optical fibers for photon collection, which suppressed accidental coincidence between-different mode photons by acting as a spatial filter because of its core size being much smaller than a multi-mode fiber.

• The Journal of the Korea Contents Association
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• v.19 no.2
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• pp.548-557
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• 2019

With the increase of single households and more women entering society, changes to lifestyle, a demand for convenience, and the recent trend for homemade meals, the market for HMR(Home Meal Replacements) is rapidly growing. This study reviewed the repurchase intentions of consumers for RTP(Ready-to-Prepare) HMR products, namely meal kits, and the moderating effect. The study found that i) ease of use increases with higher self-efficacy; ii) ease of use decreases with higher personal innovativeness, but usefulness and repurchase intentions increased; iii) repurchase intentions increase with higher social influence; iv) trust decreases with higher convenience, but repurchase intentions increased; v) trust and repurchase intentions increase with higher economic efficiency; and vi) price sensitivity has a moderating effect between trust and repurchase intentions. The outcomes of this study will not only provide a theoretical basis for a more detailed study of HMR, but is anticipated to be used as fundamental data for suggesting a direction for marketing strategies for product development and sales.

• Natural Product Sciences
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• v.27 no.2
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• pp.128-133
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• 2021

The Coumarin (1,2-benzopyrone) is the main secondary metabolite of Mikania laevigata Sch. Beep ex Baker and Mikania glomerata Spreng., which are popularly known as guaco. These plants have been used mainly in traditional medicine in the treatment of respiratory diseases because their bronchodilator effect. However, there are around 200 species of Mikania, which are quite similar in appearance. From these, only M. leavigata and M. glomerata have high concentrations of coumarins. In this line, the falsification of products Mikania based has been frequent. In this sense, this work demonstrated the application of the easy, fast, e not destructive method based in Nuclear Magnetic Resonance in quantitative mode (qNMR) for the determination of coumarin in both commercial and homemade guaco products. Thus, in the first step the compounds were extract from guaco leaves and syrups using chloroform (CHCl₃), with or without ultrasound. About the method, was linear with a R² = 0.9947 for 1,2-benzopyrone, with detection and quantification limits with were 0.11 and 0.36 mg mL^-1 respectively. In the same line, the method was safe with RSD <0.3% and with recovery ranging from 93-101%. To confirm the applicability of the method, in the last step was applied to 10 real samples (6 from leaves and 4 from syrups). The content of the coumarin in the leaf extract ranged from 0.62 to 1.30 mg mL^-1. For syrups I, II and IV, the content of coumarin was in accordance with the manufacturers. However, for de Syrup III, the concentration was 155% higher. In summary, the qNMR is a rapid method with minimal sample preparation that can be used to quantify coumarin in home-made plant extracts as well as in commercial samples as syrup for instance. This method is applicable for quality control of different plants-based products.