• Journal of KIISE
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• v.43 no.10
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• pp.1073-1078
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• 2016

(${\delta}$, ${\gamma}$)-matching for strings over integer alphabets can be applied to such fields as musical melody and share prices on stock markets. In this paper, we define ${\delta}$-approximate periods and ${\gamma}$-approximate periods of strings over integer alphabets. We also present two $O(n^2)$-time algorithms, each of which finds minimum ${\delta}$-approximate periods and minimum ${\gamma}$-approximate periods, respectively. Then, we provide the experimental results of execution times of both algorithms.

• The Plant Pathology Journal
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• v.32 no.2
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• pp.157-161
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• 2016

Gamma irradiation was evaluated for its in vitro and in vivo antibacterial activity against a postharvest bacterial pathogen, Erwinia carotovora subsp. carotovora (Ecc). Gamma irradiation in a bacteria cell suspension resulted in a dramatic reduction of the viable counts as well as an increase in the amounts of DNA and protein released from the cells. Gamma irradiation showed complete inactivation of Ecc, especially at a dose of 0.6 kGy. In addition, scanning electron microscopy of irradiated cells revealed severe damage on the surface of most bacterial cells. Along with the morphological changes of cells by gamma irradiation, it also affected the membrane integrity in a dose-dependent manner. The mechanisms by which the gamma irradiation decreased the bacterial soft rot can be directly associated with the disruption of the cell membrane of the bacterial pathogen, along with DNA fragmentation, results in dose-dependent cell inactivation. These findings suggest that gamma irradiation has potential as an antibacterial approach to reduce the severity of the soft rot of paprika.

• Journal of Life Science
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• v.14 no.1
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• pp.167-173
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• 2004

The optimal conditions for the continuous production of $\gamma$-aminobutyric acid by immobilization of Lactobacillus brevis BH-21 using column type reactor were investigated. The optimal conditions of operation were 2.2 mm diameter bead of 3.0% sodium alginate at 10 mL/h of substrate feeding rate. Continuous production by immobililzed cells showed the highest productivity with replacement of fresh medium in every 48h for fourth fermentatoin cycle following the rendition of $\gamma$-aminobutyric acid productivity. A productivity of $\gamma$-aminobutyric acid could be obtained for 25 days by continuous column type reactor under optimal conditions.

• Journal of the Korean Chemical Society
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• v.32 no.6
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• pp.575-580
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• 1988

$({\pm})-{\gamma}$-Rhodomycinone(4) and 10-Deoxy-${\gamma}$-rhodomycinone(5), late-stage Precursors of the alglycone of antitumor antibiotic Rhodomycin(2) were prepared from the cleavage of epoxide ring of 9-ethyl-9,10-epoxy-4,6, 11-trihydroxy-7,8,9,10-tetrahydronaphthacene-5,12-dione(10). The epoxide 10 was furnished from 9-acetyl-4,5,6,11,12-pentamethoxy-7,8-dihydronaphthacene(6), which was assembled utilizing ring annelation methodology developed by Hauser-Rhee.

• KSBB Journal
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• v.25 no.6
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• pp.507-512
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• 2010

In this study, we investigated the ability of luteolin, a plant derived flavonoid on hepatocarcinoma cell growth using HepG2 cell culture system. We found that luteolin increased the Smac/DIABLO releases, a mitochondrial protein that potentiates apoptosis. Luteolin also induced either transcriptional activity or expression of PPAR-gamma, a target of cancer growth that PPAR-gamma agonist sensitizes to apoptosis in certain cancer types. To find the possible upstream target molecules of PPAR-gamma activated by luteolin treatment, we used compound C, a specific inhibitor of AMP-activated protein kinase. Pre-treatment of Compound C significantly restored the activation or expression of PPAR-gamma stimulated by luteolin. This result indicated that AMPK signaling might be involved in the activation or expression of PPAR-gamma signaling pathway stimulated by luteolin. Moreover, we also found that luteolin inhibited the insulin-stimulated Akt phosphorylation as well as AICAR, a specific AMPK activator. These results propose that luteolin significantly induces cancer cell death through modulating survival signal pathways such as PPAR-gamma and Akt. AMPK signaling pathway may be an upstream regulator for survival signal pathways such as PPAR-gamma and Akt stimulated by luteolin.

• Korean journal of applied entomology
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• v.2
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• pp.38-43
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• 1963

1) These experiments were couducted to compare the effectiveness of with several new insccticides for the control of the rsce stem borer at Kimhae and Suwon in Korea from 1962 to 1963. 2) Gam ma-dol dusf and gramular were applied on the water surbul by hand and the other insecticides were sprayed on the leves of the paddy rice plaut by knap sack spayer(Table 1). 3) Gamma-dol was for the control of rice stem borers. more effective than other insecticidesused. timing for the applioation of$\gamma-dol$ was 10 days before hatching from the eggs. 4) There were no any significant differences in the effect of$\gamma-dol$ to the rice stem borer in both areas of Kimhae and Suwon.

• Macromolecular Research
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• v.11 no.5
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• pp.352-356
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• 2003

The objectives of this study were to investigate the influence of gamma irradiation for sterilization on poly(D,L-lactide-co-glycolide) (PLGA) with different molecular weight and the effect of gamma irradiation on the release behavior of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU, carmustine) from PLGA wafer with various irradiation doses. The effect of gamma irradiation on PLGA was evaluated by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and electron paramagnetic resonance (EPR). The weight average molecular weight (M$_{w}$) and glass transition temperature (T$_{g}$) of PLGA decreased after gamma irradiation. The extent of M$_{w}$ reduction was dependent on irradiation dose and PLGA molecular weight. Using EPR spectroscopy, we successfully detected gamma irradiation induced free radicals in PLGA. The gamma irradiation increased the release rate of BCNU from PLGA wafer at applied irradiation doses except 2.5 Mrad of irradiation dose in this study.study.

• KSBB Journal
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• v.8 no.3
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• pp.209-216
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• 1993

For the production of biodegradable polymers from microorganisms a bacterial strain producing a biopolymer was isolated from soil. The bacteriological characteristics of this strain and physicochemical Properties of the biopolymer produced were investigated. The bacterial strain was identified as an alkalophilic Alcaligenes sp. The Purified biopolymer treated with cetylpridinium chloride and acetone was identified as an acidic biopolymer having carboxyl groups and showed strong UV absorbance (at 210nm). The biopolymer was composed of 100% glutamic acid and glutamic acid existed as $\gamma$-polyglutamic acid($\gamma$-PGA) in the form of the $\gamma$-peptide bond. The equivalent weight of this $\gamma$-PGA was estimated about 350, indicating that one acidic fraction per 2.7 residue of $\gamma$-polyglutamic acid existed. The molecular weight was $6.5{\times}10^5$ Daltons.

• Macromolecular Research
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• v.10 no.6
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• pp.332-338
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• 2002

The effect of an electron beam and ${\gamma}$-ray irradiation on the curing of epoxy resins was investigated. Diglycidyl ether of bisphenol A (DGEBA) and diglycidyl ether of bisphenol F (DGEBF) as epoxy resin were used. The epoxy resins containing 1.0-3.() wt% of triarylsulphonium hexafluoroantimonate(TASHFA) and triarylsulphonium hexafluorophosphate(TASHFP) as initiator were irradiated under nitrogen at room temperature with different dosage of EB and ${\gamma}$-rays from a Co$^{60}$ u source. The chemical and mechanical characteristics of irradiated epoxy resins were compared after curing of EB and ${\gamma}$-ray irradiation. The thermal properties of cured epoxy were investigated using dynamic mechanical thermal analysis. The chemical structures of cured epoxy were characterized using near infrared spectroscopy. Mechanical properties such as flexural strength, modulus were measured. The gel fraction of DGEBA with ${\gamma}$-ray was higher than that of the epoxy with EB at the same dose. Young's modulus of the sample irradiated by ${\gamma}$-ray is higher than that of sample cured by EB. From the result of strain at yield, it was found that the epoxy cured by ${\gamma}$-ray had a higher stiff property compared with the irradiated by EB.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.300-306
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• 2000

In the present studies, we assessed the stability of active components and toxicological safety of irradiated Angelica gigas Nakai(Danggui). In order to confirm the stability of active components in the ${\gamma}$-irradiated roots of Danggui, the quantitative analysis of decursin and decursinol angelate of ${\gamma}$-irradiated sample was carried out by high performance liquid chromatographic (HPLC) methods using reverse phase columns and normal phase columns. From the root of Danggui, decursin and decursinol angelate were isolated by a silica gel column chromatography(toluene : ether (1 : 1), Hexane : EtOAc(15 : 1)). And then the structures were confirmed in the 1H and 13C-NMR analysis. The HPLC chromatograms of decursin and decursinol angelate in ${\gamma}$-irradiated Danggui were similar with those of non-irradiated sample. In the examination of in vitro genotoxicity of the water extract from ${\gamma}$-irradiated Danggui using Salmonella reversion assay(Ames test) and micronucleus test in Chinese hamster ovary (CHO) cells, mutagenicity was not exhibited in the two assays with or without metabolic activation. These resutls suggest that active components in the ${\gamma}$-irradiated Danggui should be stable and that the safety of ${\gamma}$-irradiated Danggui could be revealed in further test in vivo.