• Elastomers and Composites
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• v.46 no.1
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• pp.60-69
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• 2011

The various types of PBA/PMMA composite latexes were prepared by $2.1\;{\mu}m$ PBA seeded batch and seeded semi-continuous dispersion polymerization. The morphology of the PBA/PMMA composite latexes by seeded batch process was found to be closely dependant on the weight ratios of methanol/water in polymerization medium and of PBA seed/MMA at the second stage. In general, egg, snowman, confetti, peanut-like nonspherical composite latex particles were formed with increasing amount of water and MMA as a result of the occurrence of the phase separation between PBA seed and PMMA. The morphology of the PBA/PMMA composite latexes by seeded semi-continuous process was controlled by the addition time of MMA, especially, spherical shaped core(PBA)/shell(PMMA) composite latex particles were prepared under the monomer-starved condition at the second stage.

• Mycobiology
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• v.28 no.4
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• pp.165-170
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• 2000

This study was carried out to obtain the basic data for artificial culture of veiled lady mushroom (Dictyophora spp). The optimal conditions for the mycelial growth were $25^{\circ}C$ and pH 5.0 for all isolates except the optimal temperature of $30^{\circ}C$ for D. echinovolvata ASI 32002 and Phallus rugulosus. The optimal medium for Dictyophora spp. was PBA (potato bamboo sawdust extract agar) medium. The strain ASI 32002, D. echinovolvata, grew faster than. D. indusiata ASI 32003 and Phallus rugulosus ASI 25007 on the medium. Carbon sources such as glucose, maltose and inuline were favorable for stimulating a mycelial growth of the two strains of ASI 32002 and ASI 32003. Asparagine and glutamine appeared to be favorable to the strain ASI 32002 and ASI 32003, where as alanine, one of nitrogen source also favorable to the strain ASI 32002. The optimum C/N ratio of the two isolates of ASI 32002 and ASI 32003 was about 25 : 1 when 2% glucose as carbon source was mixed with the basal medium. While, in the case of 4% as carbon source, the optimum C/N ratio was about 30 : 1.

• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.293-298
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• 2017

BACKGROUND: Pyrethroids (PYRs) are a widely used insecticide in agriculture and household area. In mammals, PYRs such as deltamethrin is metabolized to 3-phenoxybenzoic acid (3-PBA) in liver that is mainly excreted in urine. This study is designed to single exposure of deltamethrin to rats in a dose-dependent manner and identify the correlation between deltamethrin exposure and its metabolite (3-PBA) in urine. METHODS AND RESULTS: Exposure levels of deltamethrin were control (0 mg/kg bw), low (0.0705 mg/kg bw), medium (0.705 mg/kg bw) and high (7.05 mg/kg bw) dose. Low concentration was derived by ussing Korea predictive operator exposure model (KoPOEM). Dermal exposure persisted for 6 h, and urine specimens were collected for 24 h. The urine matrix was removed after a series of procedures and 3-PBA was analyzed by gas chromatography/mass spectrometry. CONCLUSION: There was a strong correlation ($R^2=0.83$) between the amount of oral exposure to delta me thrin and urinary levelof3-PBAexcreted. In dermal exposure groups of deltamethrin except high-dose, also there was a good correlation between urinary 3-PBA and deltamethrin exposure, but not stronger than in oral deltamethrin exposure groups. Based on these results, therefore, the amount of 3-PBA in urine can be used as a good monitoring indicator that reflexing the exposure level of deltamethrin to human body.

• Journal of Mushroom
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• v.3 no.2
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• pp.45-51
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• 2005

This study was carried out to obtain the basic data on artificial culture of Sparassis crispa. The mycelial growth and density were good in the PBA, PDA and PDM media, and especially prominent in the PBA medium. The optimum condition for the mycelial growth was $25^{\circ}C$ and pH 5.0, respectively. The carbon sources such as glucose, fructose, mannose, xylose(monosaccharide) and maltose(disaccharide) were favorable to mycelial growth of S crispa. The optimal concentration of glucose is 1.0~1.5%. As nitrogen sources, threonine, peptone, glycine, glutamine and valine appeared to be favorable to the mycelial growth and density. The optimal concentration of peptone is 0.3%.

• Journal of Korea Multimedia Society
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• v.12 no.12
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• pp.1769-1777
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• 2009

With the advent of the ubiquitous technology age, the progress of network technology has enabled a robust sensor communication, not just in cities, but also in poor surroundings such as deserts, polar regions, or underwater environments. In this paper, we propose a Multiple Acknowledgement (MA) technique to replace the conventional Automatic Repeat request (ARQ) technique. The MA mechanism is to send an Ack to many receivers simultaneously. The CH (master, coordinator) of the unit cluster broadcasts a Beacon frame where Ack information of the previously transmitted data is included. This technique can reduce the number of transmissions and overhead significantly. The proposed technique is a scheme improving the efficiency of an underwater sensor network where the uplink data transmission is the mainstream. The Performance of the ARQ, Block Ack, Pervasive Block Ack and the proposed method were compared with one another and analyzed. The proposed method showed significant performance improvement as compared with the ARQ, BA, and PBA in its channel efficiency.

• Journal of Plant Biotechnology
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• v.3 no.2
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• pp.95-100
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• 2001

To select the section with shoot formation ability, the calli and shoot formation from three sections (first leaf including cotyledonary node, hypocotyl and cotyledon explants) of 5-days-seedlings of soybean were induced on MS medium supplemented with 1.0 mg/L BAP, 3% sucrose, and 0.3% gelrite for one month. The first leaf section exhibited the highest shoot formation rate (51%), followed the hypocotyl section (10%) and the cotyledon section (0%). The shoot formation rates and shoot number of the four excised sections (whole first leaf, a half of the first leaf, a third of the first leaf and only node) of the first leaf were also investigated on the same medium. A half of the first leaf explant and the third of the first leaf explant had higher shoot formation rates (76-80%) and numbers (3-4 / explants) than those in other two explants. Effects of six cytokinins (kinetin, zeatin, BAP, 2iP, PBA, and TDZ) on shoot formation were determined, using the half of the first leaf explants. Zeatin (1.0 mg/L) exhibited the highest in shoot formation rate (94%) and numbers (8 / explant). In addition, the combined effects of three cytokinins (zeatin, BAP, and TDZ; 0.5, 1.0, 2.0 mg/L, respectively) and an auxin (IAA; 0.0, 0.5, 1.0, 2.0 mg/L) were determined. The combination (1:1, v/v) of zeatin (1.0 mg/L) and IAA (1.0 mg/L) exhibited the highest in shoot formation rate (96%) and numbers (16 / explant), twice more than zeatin (1.0 mg/L) alone. The shoot cuttings were transferred and cultivated on the rooting media supplemented with only auxin, IBA at various concentrations. The highest root formation (8 / shoot) was achieved on the medium supplemented with 1.5 mg/L. After 4 weeks of cultivation, the plantlets with an extensive root system were transplanted in pots with a soil mixture of vermiculite and fine sand. Transferred to field, about 75% of the plantlets survived.

• The Korean Journal of Mycology
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• v.35 no.2
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• pp.81-84
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• 2007

In some cases, the problem with the mycelium of Tricholoma giganteum is delayed mycelial growth or non-regeneration. Therefore, this study was conducted to understand the mycelial storage condition of T. giganteum and to investigate the regeneration ratio of mycelial growth. T. giganteum obtained from KACC in RDA was evaluated for its simple preservation at $10^{\circ}C$ and subcultured on different media. Mycelium of T. giganteum was cultured on the PBA (potato bamboo extract medium) for seven days at $30^{\circ}C$. Using simple preservation method, the mycelium of T. giganteum (MKACC 50852) and Pleurotus ostreatus (Chunchu No. 2) were stored on six different media in two kinds of storage vessels (tube and vial) for a period of 1-12 months at $4^{\circ}C,\;15^{\circ}C$, and $25^{\circ}C$ storage temperatures. At $4^{\circ}C$ storage condition, mycelial regeneration was failed in all agar media, but was successful in the sawdust medium for 3 months. At $15^{\circ}C$ storage, mycelial activity was maintained up to six months. On the other hand, P. ostreatus produced well-regenerated mycelia both at $4^{\circ}C$ and $15^{\circ}C$ storage up to 12 months. In conclusion, it is estimated that the mycelia storage condition of T. giganteum must be done at $15^{\circ}C$ and subcultured within six months.