• Microbiology and Biotechnology Letters
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• v.29 no.4
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• pp.212-220
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• 2001

Rare mating was used to select a respiratory deficient mutant of Saccharomyces cerevisiae HDC52 strain. Glucoamylase gene of S. diastaticus K114 was developed into the RD mutant which could uptake maximum amount of non-fermentable sugars through the expression of glu- coamplyase gene and the fermentation characteristics of the developed strain HCS were investigated. The size of HCS yeast and HBD52 yeast strain were 13 $\mu\textrm{m}$ and 10$\mu\textrm{m}$ respectively. HCS strain which can uptake maximum amount of non-fermentable sugar through the expression of glucoamylase gene was developed. By karyotype anal- ysis. HCS stain but not RD mutant HBC52 showed a band of 1150 kb chromosome DNA This band should include glcoamylase gene from Saccharomyces diataticus K114 THis strain has glucoamylase which can degrade starch By transduction and contrnuance of glucoamylase gene HCS strain gegraded strach and formed halo. Also, HCS strain maintained the character after 50 generations. Glucoamylase activities of Saccharomyces diastaticus K114 and HCS yeast strains are 9.5 and 2.7~3.4(unit/ml) HCS and HBC52 strain showed similar sugar fermentation patterns and low flocculation In spore and film forming test, HCS and HBC52 strain formed neither spores nor films. In the limit fermentation test, HBC52 strain showed fermentation level of 68% and HCS strain showed 76~78% As the limit attenuation of HBC52 and HCS were ($2.00^{\circ}$P) and ($0.7~0.93^{\circ}$P) This study demon- strates and HCS strain may be used for low carbohydrate beer fermentation.

• Journal of The Korean Astronomical Society
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• v.46 no.6
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• pp.253-259
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• 2013

We present near-infrared light curves of HBC 722 after its the September 2010 outburst. We have been monitoring its near-infrared light curves since November 2010 with Korean Astronomy and Space Science Institute Infrared Camera System (KASINICS). HBC 722 exhibits large changes in optical and near-infrared brightness since its outburst. The J, H, and $K_s$ light curves over about 2.5 years show that in all observed bands HBC 722 progressively became fainter until around April 2011, down to J ~10.7, H ~9.9, $K_s$ ~9.3, but it is getting brighter again. Large scatter in the obtained light curve prevents us from finding whether there is any short timescale variation as reported in other optical observations. The near-infrared color of HBC 722 is becoming bluer since its outburst. The pre-outburst Spectral Energy Distribution (SED) of HBC 722 is consistent with that of a slightly reddened Class II YSO with the exception of the extraordinary IR-excess in the far-infrared region.

• Journal of Genetic Medicine
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• v.9 no.1
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• pp.1-10
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• 2012

About 7% of all breast cancer (BC) cases result from a genetic predisposition, and approximately 1,000 patients develop hereditary BC (HBC) every year in Korea. BRCA1 and BRCA2 are the primary genes underlying HBC. The average cumulative risks in BRCA1 mutation carriers at 70 years of age are 65% (95% confidence interval 44-78%) for BC and 39% (18-54%) for ovarian cancer (OC). The corresponding estimates for BRCA2 are 45% (31-56%) and 11% (2.4-19%), respectively. The penetrance of BRCA mutations is not the same between patients and can depend on factors such as race and birth-cohort. The Korean Hereditary Breast Cancer (KOHBRA) study is a large prospective nationwide study that includes 39 participating centers. Between May 2007 and May 2010, the first phase of the KOHBRA study was planned and fulfilled successfully. The primary aim of phase I was to estimate the prevalence of BRCA1/2 mutations and OC among a high-risk group of patients with HBC and their families. According to data collected during phase I of the study, the prevalence and penetrance of BRCA mutations were comparable to corresponding data from Western countries. For the second phase of the KOHBRA study, we are currently investigating a Korean BRCA mutation prediction model, prognostic factors in BRCA-related BC, environmental/genetic modifiers, and implementing a genetic counseling network. The final goal of the KOHBRA study is to create clinical practice guidelines for HBC in Korea. In this article, I review the genetics of HBC, summarize the characteristics of Korean HBC, and discuss current and future HBC research in Korea.

• Journal of the Korean Professional Engineers Association
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• v.21 no.2
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• pp.1-12
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• 1988

• Journal of the Korean Professional Engineers Association
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• v.25 no.1
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• pp.105-111
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• 1992

• Journal of the Korean Professional Engineers Association
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• v.23 no.3
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• pp.79-82
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• 1990

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.649-652
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• 2008

In this paper, the applicability of hwangtoh, as an alternative of cement paste, is investigated for the solution of internal heat and shrinkage caused by the hydration of cement paste. Several small-sized specimens of hwangtoh and ordinary portland concrete(OPC) were compared as to compressive strength, heat of hydration, and shrinkage strain. Moreover, the applicability of mass structure was reviewed through the test of large-size specimens. The 28-day compressive strength of hwangtoh concrete(HBC), ranged 18 to 33 Mpa, can reach that of ordinary portland concrete. Not only the maximin internal temperature of HBC was read about 1/4 of OPC as it is cured, but also its drying shrinkage decreased as lower as 50% of OPC starting from 60 days. Therefore, hwangtoh binder is more favorable than cement one in the view of hydration heat and shrinkage under the construction of mass structures.

• Korean Journal of Microbiology
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• v.27 no.3
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• pp.169-175
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• 1989

To study the role of mutant precore region in expression and secretion of hapatitis B viral core antigen, we have cloned core antigen gene(HBc) with or without precore region in geterologous expression vectors containing SV40 promoter, yeast promoter, and lambda $P_{L}$ promoter. In COS cells transfected with plasmid containing C-gene with precore region, antigens were detected in both cell extract and cultured medium. However, in the cells transfected with plasmids containing C-gene without precore or with mutated precore region by one nucleotide (T) addition at the nucleotide 1,821, HBcAg was detected only in cell extracts. These results support that the mutation by one nucleotide addition shifted the initiation codon of precore region to 53 nucleotides upward and the elongated precore region also played a major role in the secretion of HBcAg in mammalian cells. In the case of yeast and E. coli, HBcAg was detected only in cell extracts in spite of the presence of precore region, which suggest that precore region could not affect HBcAg secretion in these system.

• Journal of Microbiology and Biotechnology
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• v.19 no.4
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• pp.416-423
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• 2009

Hepatitis B core antigen(HBcAg) is an important serological marker used in the diagnosis of hepatitis B virus(HBV) infections. In the current study, a fast and efficient preparative purification protocol for truncated HBcAg from Escherichia coli disruptate was developed. The recombinant HBcAg was first captured by anion exchange expanded bed adsorption chromatography integrated with a cell disruption process. This online capture process has shortened the process time and eliminated the "hold-up" period that may be detrimental to the quality of target protein. The eluted product from the expanded bed adsorption chromatography was subsequently purified using size-exclusion chromatography. The results showed that this novel purification protocol achieved a recovery yield of 45.1% with a product purity of 88.2%, which corresponds to a purification factor of 4.5. The recovered HBcAg is still biologically active as shown by ELISA test.

• Journal of The Korean Astronomical Society
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• v.44 no.2
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• pp.67-72
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• 2011

We report the results of our high resolution optical spectroscopic monitoring campaign (${\lambda}$ = 3800 ~ 8800 ${\AA}$, R = 30000 - 45000) of the new FU Orionis-type object HBC 722. We observed HBC 722 with the BOES 1.8-m telescope between November 26 and December 29, 2010, and FU Orionis itself on January 26, 2011. We detect a number of previously unreported high-resolution K I and Ca II lines beyond 7500 ${\AA}$. We resolve the H${\alpha}$ and Ca II line profiles into three velocity components, which we attribute to both disk and outflow. The increased accretion during outburst can heat the disk to produce the relatively narrow absorption feature and launch outflows appearing as high velocity blue and red-shifted broad features.