• Journal of Microbiology and Biotechnology
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• v.19 no.9
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• pp.966-971
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• 2009

Peroxidase from Coprinus cinereus (CiP) has attracted attention for its high specific activity and broad substrate spectrum compared with other peroxidases. In this study, the functional expression of this peroxidase was successfully achieved in the methylotrophic yeast Pichia pastoris. The expression level of CiP was increased by varying the microbial hosts and the expression promoters. Since a signal sequence, such as the alpha mating factor of Saccharomyces cerevisiae, was placed preceding the cDNA of the CiP coding gene, expressed recombinant CiP (rCiP) was secreted into the culture broth. The Mut Pichia pastoris host showed a 3-fold higher peroxidase activity, as well as 2-fold higher growth rate, compared with the $Mut^s $ Pichia pastoris host. Furthermore, the AOX1 promoter facilitated a 5-fold higher expression of rCiP than did the GAP promoter.

• Journal of information and communication convergence engineering
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• v.6 no.3
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• pp.348-352
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• 2008

In distributed computing paradigm, mobile surrogate systems migrates from on host in a network to another. However, Mobile surrogate system have not gained wide acceptance because of security concerns that have not been suitably addressed yet. In this paper, we propose a security framework based on Grid Proxy Gateway for mobile Grid service. The current Grid Security Infrastructure is extended to mobile computing environments. The surrogate host system designed for mobile Personal Digital Assistant (PDA) users can access the certified host and get his proxy credential to launch remote job submission securely.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.178-181
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• 2001

The organic light-emitting devices (OLEDs) based on fluorescence have low efficiencies due to the requirement of spin-symmetry conservation. By using the phosphorescent material, the internal quantum efficiency can reach 100 %, compared to 25 % in the case of the fluorescent material. Thus, the phosphorescent OLEDs have recently been extensively studied and showed higher internal quantum efficiencies then the conventional OLEDs. In this study, we investigated the characteristics of the phosphorescent OLEDs, with the green emitting phosphor, Ir(ppy)$_3$ (tris(2-phenylpyridine)iridium). The devices with a structure of ITO/TPD/Ir(PPy)$_3$ doped in the host material/BCP/Alq$_3$/Li:Al/Al were fabricated, and its electrical and optical characteristics were studied. By changing the doping concentration of Ir(PPy)$_3$ and the host materials, we fabricated several devices and investigated the device characteristics.

• Fisheries and Aquatic Sciences
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• v.1 no.1
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• pp.63-67
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• 1998

The host finding behavior of Entobdella hippoglossi oncomiracidium, skin parasite of the Atlantic halibut was investigated. Almost of the parasite swam downward from the top to the bottom of the 150cm glass tube within 30 minutes. The average swimming speed of oncomiracidium was $0.32\pm0.10cm/second$ throughout the experiment. When the parasites arrived on the bottom of the glass tube, they moved upwards and downwards continuously within the 10cm of the bottom. This behavior would suggest that it may be one of the essential methods for host searching of the parasite. When the oncomiracidia was exposed different stimuli, they responded positively light and halibut mucus.

• The Korean Journal of Ecology
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• v.19 no.6
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• pp.575-582
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• 1996

Molipteryx fuliginosa (Uhler, 1860) is a plant juice sucker which feeds on new tips of Rubus oldhami Miquel and Zelkowa serrata Makino, and it has a strong preference for teses two plants in Korea. M. fuliginosa has one generation a year and hibernates as a young adult. Most of the winter survivors emerge in early May. It is the first time their host plants were found and reported. Females mainly lay their eggs one by one separately on the leaves of R. oldhami, and even on the steel wire, the lid guaze and the ground in the laboratory. Nymphs do not gather, but stay on the hatching site, Nymphs except the non-feeding first instar feed on young shoots. From the second to the fifth instar nymphs migrate to the upper part of the shoot and congregate in part on an expanded leaf. The new adults first appeared on 11 August, and remained in the host plant, and fed on until mid October. The duration of the hatching and molting, and the survivorship curve based on the laboratory rearing were determined.

• Journal of The Korean Astronomical Society
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• v.23 no.2
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• pp.116-121
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• 1990

It has been suggested that there could be a large number of primordial black holes which were formed in the early universe. We analyze the growth of such a primordial black hole following two different accretion rates - the Eddington accretion rate and the Bondi accretion rate - at the center of a host star like the sun. We find that a primordial black hole with M < ${\sim}10^{17}\;g$ cannot substantially grow in any case throughout the lifetime of a host star. If M > ${\sim}10^{17}\;g$, the evolution of a host star depends entirely on the mode of accretion, but it ends as a black hole in either case. Since more stars may have primordial black holes at the center of a galaxy this may result in a cluster of such black holes, and the cluster may eventually collapse to produce a single supermassive black hole.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.202-205
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• 2000

A gene coding $endo-{\beta}$,-1, 4 glucanase from Actinomyces sp. KNG40 and phytase from Hansenula polymorpha were cloned into Esherichia coli JM101 by using E. coli/Lactobacillus shuttle vector pNZ3004 and pNZ123. The plasmid p3PS(1-4) and p123(1-4) have slpA promoter and slpA signal sequence. So, I constructed expression vectors, p3PS(1-4)Endo, phy and p123(1-4)Endo, phy. These constructed vector was transformed in target host Lactobacillus gasseri and reutri. These transformed host expressed endoglucanase and phytase as extracellular fraction. In the enzyme activity of the same vector, host L, gasseri was higher activity than L. reuteri. This indicates that L. gasseri recongnize promoter and signal sequence very well.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.376-379
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• 2000

The methylotrophic yeast Pichia pastoris is one of the best host for the production of foreign proteins because of the presence of the strong AOX1 promoter induced by methanol. Methanol feeding induces the protein production and provides energy sources for the host cells. However, excess methanol inhibits the growth of host cells, while an insufficient methanol lead to poor growth and protein production. We have used various controled methanol feeding strategies to obtain the maximum proteins.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.465-468
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• 2008

New green light emitting phosphorescent devices with host structure of TCTA[4,4',4"-tris(N-carbazolyl)-triphenylamine]/$TCTA_{0.5}TPBi_{0.5}$/TPBI[1,3,5-tris(N-phenylbenzimiazole-2-yl)benzene] were proposed and investigated according to the thickness combination of host layers and the doping level of $Ir(ppy)_3$[tris(2-phenylpyridine) iridium(III)].

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.153-153
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• 2010

We have developed blue phosphorescent organic light emitting diode using spin-coated poly(9-vinylcarbazole) (PVK) host layer doped with blue phosphorescent material, Iridium(III) bis(4,6-difluorophenyl)-pyridinato-N,C2) picolinate (FIrpic). the concentration of FIrpic dopants was varied from 2% to 10%. The electrical and optical characteristics of the blue phosphorescent OLED with PVK:FIrpic layer were investigated.