• Microbiology and Biotechnology Letters
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• v.12 no.4
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• pp.305-309
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• 1984

A selective medium which allows growth of only cellulolytic bacteria was developed. The medium composed of 0.5% carboxymethylcellulose (CMC), 0.005% yeast extract, minerals and agar. Colony formation on this medium indicates overall activities of cellulose utilization. A subsequent test with Congo Red dye could distinguish extracellular cellulolysis from intracellular type.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.283-291
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• 2012

Bioremediation efforts often rely on the application of surfactants to enhance hydrocarbon bioavailability. However, synthetic surfactants can sometimes be toxic to degrading microorganisms, thus reducing the clearance rate of the pollutant. Therefore, surfactant-resistant bacteria can be an important tool for bioremediation efforts of hydrophobic pollutants, circumventing the toxicity of synthetic surfactants that often delay microbial bioremediation of these contaminants. In this study, we screened a natural surfactant-rich compartment, the estuarine surface microlayer (SML), for cultivable surfactant-resistant bacteria using selective cultures of sodium dodecyl sulfate (SDS) and cetyl trimethylammonium bromide (CTAB). Resistance to surfactants was evaluated by colony counts in solid media amended with critical micelle concentrations (CMC) of either surfactants, in comparison with non-amended controls. Selective cultures for surfactant-resistant bacteria were prepared in mineral medium also containing CMC concentrations of either CTAB or SDS. The surfactantresistant isolates obtained were tested by PCR for the Pseudomonas genus marker gacA gene and for the naphthalene-dioxygenase-encoding gene ndo. Isolates were also screened for biosurfactant production by the atomized oil assay. A high proportion of culturable bacterioneuston was tolerant to CMC concentrations of SDS or CTAB. The gacA-targeted PCR revealed that 64% of the isolates were Pseudomonads. Biosurfactant production in solid medium was detected in 9.4% of tested isolates, all affiliated with genus Pseudomonas. This study shows that the SML is a potential source of surfactant-resistant and biosurfactant-producing bacteria in which Pseudomonads emerge as a relevant group.

• The Plant Pathology Journal
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• v.23 no.1
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• pp.3-6
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• 2007

Chickpea wilt caused by Fusarium oxysporum f. sp. ciceris(FOC) is the most destructive disease in India. It is seed-borne as well as soil-borne pathogen. The role of seed-borne FOC in introducing and establishing wilt in FOC free soils is unknown. Using seeds of FOC infected chickpea cultivar K 850, we provided an evidence of establishing wilt disease in the FOC free soils within three crop cycles or seasons. In the first cycle, typical wilt symptoms were observed in 24 pots in 41 days after sowing. These 24 pots were used for second and third cycles without changing the soil. These 24 pots were sown with seeds collected from healthy plants of a susceptible cultivar JG 62, one seed per pot and development of wilt symptom was recorded. Wilt symptoms appeared in all the pots 26 days after sowing in second cycle and in 16 days after sowing in third cycle. On selective medium, all of the wilted plants yielded FOC in all the three cycles indicating that the mortality was due to wilt. FOC propagules on selective medium were 172, 1197, and 2280 $g^{-1}$ soil at the end of the first, second, and third cycles, respectively. These studies indicated that Fusarium wilt of chickpea is seed-borne and seeds harvested from wilted plants when mixed with healthy seeds can carry the wilt fungus to new areas and can establish the disease in the soil to economic threshold levels within three seasons.

• Korean Journal of Plant Resources
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• v.18 no.2
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• pp.351-358
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• 2005

The effects of thiamine-HCl or polyvinylpyrrolidone (PVP) on growth and catechin contents of calli from Camellia sinensis leaves were investigated to improve catechin productivity in callus cultures on the selective medium. The growth of calli was great on the proliferation medium (the MS medium with 0.2 mg/L 2,4-D and 1.0 mg/L TDZ) supplemented with $20{\sim}30\;mg/L$ thiamine-HCl. Although the caffeine content was low in calli compared to young leaves, the total content of catechins was high in calli. Particularly,(-)-epicatechin (EC) which not detected in young loaves was also detected in calli on the propagation medium containing thiamine-HCl or PVP. In addition, the (-)-epicatechingallate (ECG) content was significantly higher in calli than in young leaves. In conclusion, the proliferation medium supplemented with 30 mg/L thiamine-HCl as a vitamin source seemed to be optimal condition for the growth and catechin production in callus culture.

• Microbiology and Biotechnology Letters
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• v.19 no.2
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• pp.135-139
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• 1991

Tridecanedioic acid (DC-13), starting material of the valuable musk ethylene brassylate, was obtained from n-tridecane by the Candida tropicalis mutant. The mutants were first obtained from primary screening step using the selective medium and then solid phase extraction sampling method was used for the selective isolation of organic acids from the cultured media of mutants. The resulting acids were directly converted to volatile tert-butyldimethyl silyl delivatives, which were then analyzed by gas chromatography. The efficient GC profiling method was used for the rapid identification of the mutant producing DC-13 in large quantity, and for the optimization of the culture conditions of mutant. The optimal culture conditions were found as follows: pH 8.0, 30$^{\circ}C$, 250rpm, 48hour of culture and $(NH_4)_2HPO_4$ as nitrogen source.

• Proceedings of the KIEE Conference
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• 2003.07e
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• pp.62-69
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• 2003

In recent years, data transmission using power lines has been much highlighted. Power line is known to be cost-effective communication medium because the entire cable infrastructure has been already established and it is entirely connected with any home. Recently, the target of researches is to communicate data reliably over power lines at the speed of at least 1Mbits/s over the frequency range from 1MHz to 10MHz. OFDM communication system has been used for the high speed data transmission. Next, the conventional and adaptive OFDM systems for high speed data transmission over power line channel are investigated. The performance of AOFDM(adaptive OFDM) over the frequency selective channel with impulsive and narrow-band noise are studied to be a nice solution for high speed data transmission over power lines. The simulation results show that data the rates of the AOFDM are improved about 47% more than the ones of the conventional OFDM over the frequency response of case 4. In the results, the data rate has been much improved by the proposed adaptive algorithm in the frequency selective channel.

• Korean Journal of Microbiology
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• v.11 no.2
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• pp.101-106
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• 1973

The microwave of 2450 MHz, generated by a household cooking oven, was evaluated for its applicability to melt various rehydrated media and to remove dissolved oxygen from tubed media for anaerobic culture. The effect on the sterilization of E. coli in selective media was also evaluated. The following results were obtained. 10 The microwave oven was useful in saving time for melting media and in eliminating heat and combustion gas from the laboratory, which were inevitable by-products in the conventional flame method. 2) Dissolved oxygen could be removed without boiling over by exposing the tubes of anaerobic culture medium after putting them in a wire basket in a beaker with water. 30 The count of E. coli during the melting of MacConkey and EMB agar were similar to those treated with open flame. The microwave treatment was not considered a possible mean to replace autoclaving even in these selective media.

• YAKHAK HOEJI
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• v.44 no.5
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• pp.379-383
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• 2000

Stanozolol (STZ, 17$\alpha$-methyl-17$\beta$-hydroxy-5$\alpha$-androstano-(3,2-c) pyrazole), an anabolic steroid, is an abused drug by body-builders or atheletes, as well as medicine for treatment of aplastic anemia and vascular thrombosis. In human volunteers, the major urinary metabolite of STZ was reported to be 3'-hydroxystanozolol that was identified by gas chromatography-mass selective detector (GC/MSD). The objective of this experiment is to investigate the in vitro metabolism of STZ in liver S-9 faction of polychlorinated biphenyl-induced rats. Reaction mixture including STZ as substrate and the S-9 faction was extracted with diethyl ether and quantified by the selected ion monitoring mode of GC/MSD. The selected concentration of substrate STZ is 100 nmole and the selected time for incubation in the reaction mixture was determined to 60 min. The amount of 3'-hydroxystanozolol produced was increased by about 6-fold in the reaction medium including the liver S-9 fraction of polychlorinated biphenyl-induced rats, compared to that of untreated rats. Inhibitors of cytochrome P450, SKF-525A and 7,8-benzoflavone, decreased the production of 3'-hydroxystanozolol by about 89~100% and 65~75%, respectively; In conclusion, hydroxylation of STZ into 3'-hydroxystanozolol is confirmed by GC/MSD and is catalyzed by cytochrome P450.

• Korean Journal of Microbiology
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• v.28 no.2
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• pp.98-103
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• 1990

Brevibacterium lactofermentum SWA (arg trp) and B. lactofermentum SWB (met ser) were obtained from UV and NTG treatment. The rates of protoplast formation by B. lactofermentum SWA and SWB were 99.93% and 99.98%, respectively when each strain was treated with penicillin G in mid exponential growth phase, followed by incubation with 400 $\mu\textrm{g}$/ml of lysozyme in lysis fluid supplemented with 0.4M sucrose. Frequencies of protoplast regeneration in B. lactofermentum SWA and B. lactofermentum SWB were 9.27% and 10.32% respectively, on regeneration medium containing 0.5M sodium succinate, 50 mM $Mg^{2+}$, and 3% PVP. In intraspecific protoplast fusion between B. lactofermentum SWA and B. lactofermentum SWB, fusion frequency of $2.30\times 10^{-5}$ was observed by using the 100mM $CaCl_{2}$ and 30% PEG 6,000 in fusion fluid. Relative recombinant frequencies in each marker by means of selective media could be used for genetic analysis.

• Korean Institute of Interior Design Journal
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• v.24 no.6
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• pp.145-153
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• 2015

For this research with the objects of spaces in two department stores which can be referred to as representative facility of commercial space, observation test has carried out to estimate how much visitors rivet their eyes to the display of shops. In addition, to find out what effect the difference among the department types has on the selective attention to space element, the observation time was applied as a medium for estimation. The followings are the result from analyzing the observation frequency and the observation intensity feature of each section where the characteristics of design could be found at attention. First, both images of A and B had concentrative dominant-observation at left shops. In case of Image A, Customers began to observe the right shops very attentively after 25 seconds, and with Image B, the attentive observation at right and left took place alternatively after 35 seconds. In other words, regardless of the characteristics of shop displays, the left shops were observed first while in case of the observation after the early and middle time-frame the characteristics of shops were found to have effects on observation. Second, the normal observation showed some difference among attention sections over time while on the whole both images of A and B had the same highly attentive observation at the middle space. Accordingly, it could be concluded that the middle space was playing a faithful role as background for commercial spaces. Third, the ignorant observation, which is the opposite to the attentive observation, was found different between the images of A and B. When the ignorant observation is considered to have intentionality, it will be possible to set up the display which may attract the attention aggressively by the process of figuring out the characteristics of ignored shops.