• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.475-481
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• 1999

Yeast extracts were prepared using either autolysis or enzymatic digestion methods for industrial application of the Saccharomyces cerevisiae B24 strain developed previously to have high RNA content. Extraction ratio of yeast extract from yeast cell reached 65% when autolysis of yeast slurry having 10% solid content was induced at $50^{\circ}C$ and pH 5.0 by agitating with 100 rpm. However, neither 5'-IMP nor 5'-GMP was detected from the autolyzate. In another attempt to prepare a yeast extract S. cerevisiae B24 culture was treated at $90^{\circ}C$ and then treated by various enzymes including ${\beta}-1,3-glucanase$, phosphodiesterase (nuclease P1), adenylic deaminase, and a protease. The yeast extract prepared by the enzymatic digestion method contained 3.2g of 5'-IMP and 5'-GMP/100g dry yeast extract.

• Convergence Security Journal
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• v.5 no.2
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• pp.19-27
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• 2005

As home network is increasing to use, home network industry is developing too. Also, it is to be a popular subject in the network's topics. In this reasons, home network become a important thing because home gateway function is working between access network and home network. In the home network, it relates on the personal computer, home pad, and digital television. But, home gateway is not prepared standard point about techniques. Therefore, many kind of technique want to try for developing of home gateway's functions. Usually, we use ID/PASSWORD method in network control system. But, we found a lot of problems about classical network system while we experienced Jan/25 big trouble. We are considering about that home network system are using same network net. Therefore, seriously we have to check about security and safety at the home network's environment. This report focus on the home network's environment to control for using and efficiency and then it wants to find ways to protect from the internal and external attacks. Existing ID/PASSWORD method it used a electronic signature and the security against the approach from of external watch, the MIB structure of role base and the security of the Home network which leads the authority control which is safe even from the Home network inside it strengthened it used compared to it proposed.

• Journal of the Korea Institute of Building Construction
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• v.11 no.6
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• pp.597-608
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• 2011

It has been often noted as a problem that as there are no objective and clear criteria for the repair cost estimate of persistent defects, when a claim arises in relation to an apartment construction, significantly different amounts of compensation may be given for similar defects based on the experience and tendencies of the construction experts asked to make a judgment. For this reason, this research aims to present defect managers with a more reasonable and objective estimation criteria and a system to determine the repair cost of defects based on an analysis of relevant factors. The research findings show that the historical cost system is applied first, and then a standard of estimation is used to estimate the cost for the items that are not included in the historical cost system. The criteria for the repair cost for each defect is as follows: the repair cost for defects arising from a regulation violation is determined by calculating the reconstruction cost of the parts in question after demolishing them; the repair cost for progressive defects is determined based on a contribution ratio proportional to the age of the building; the repair cost for repetitive defects is calculated by considering an alternative to maximize the intended function of the defective parts; and the repair cost for value depreciation defects is determined based on the ratio of the warranty period to the lapsed years. However, repair cost estimation for dual value depreciation defects should be studied in future research.

• Journal of the Korean GEO-environmental Society
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• v.15 no.7
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• pp.23-30
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• 2014

This paper deals with the characteristics of deformation of the underground corrugated steel plate culverts constructed in the areas where the minimum depth of within 1.5 m soil cover is not secured in the bottom of highways. The underground corrugated steel plate culverts at shallow depth are often designed and constructed with the consideration of the minimum depth of soil cover according to the design standards, which was made in order to minimize any deformation. Additionally, if under unfavorable conditions, slabs are set up for stress relaxation to disperse and minimize the weight of loads transferred to the corrugated steel plate culverts. Nevertheless, if the underground corrugated steel plate culverts are built in areas where the minimum depth of soil cover inevitably cannot be secured, there may occur some deformation. In this paper, a research was carried out to identify the characteristics of deformation in areas where the minimum depth of soil cover is not secured. The result shows that there existed the deterioration of pavement and in its smoothness around the corners of slabs for stress relaxation. To this end, this paper studied the structural stability of the underground corrugated steel plate culverts established in the areas with no minimum depth of soil cover secured, with the consideration of causes and solutions of pavement deterioration.

• Journal of the Korean Wood Science and Technology
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• v.12 no.1
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• pp.11-30
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• 1984

This study was executed to offer the basical data needed to the plywood industry as examining on the wood characteristics of veneer species that grow in Korea. According to the aggravation of log import from foreign countries caused by the gradual exhaustion of wood resources in recent years, the study on wood characteristics of veneer species growing in Korea should be carried out preferentially in promotion of the domestic timber utilization and development of it's processing technique for plywood industry. 50 commercial veneer species in this study were selected from 33 genuses, and general macroseopical wood characteristics for them were examined and described by the species. And also keys for the identification based on gross features were briefly prepared and presented by gymnosperm and angiosperm respectively.

• Journal of Life Science
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• v.18 no.1
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• pp.136-142
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• 2008

A recombinant Pichia pastoris carrying double expression cassette of Rhodotorula glutinis epoxide hydrolase(RgEH) gene was developed and used for preparing enantiopure (S)-styrene oxide from racemic mixture of styrene oxide. BglII restriction site of original RgEH gene (pPICZ B/RgEH #2) of previous report was mutated using PCR technique for the construction of double expression cassette containing promoter ($P_{AOX1}$), EH gene and transcription terminator ($TT_{AOX1}$) in pPICZ C vector. Double expression cassette with RgEH was inserted into the chromosomal DNA of P. pastoris. $V_{max}$ ($2.2{\mu}mol\;min^{-1}mg\;dcw^{-1}$) on (R)-styrene oxide of P. pastoris with double expression cassette was about 6-fold higher than that ($0.4{\mu}mol\;min^{-1}mg\;dcw^{-1}$) of P. pastoris with single expression cassette. For the determination of the optimal condition, the effects of detergent and temperature on the enantioselective hydrolytic activity and yield of the enantiomer were investigated. When the reaction was performed at $10^{\circ}C$ for 10 min in the presence of 0.5% Tween 20, enantiopure (S)-styrene oxide with 99.9% ee was obtained as the yield 43.4 % from 20 mM racemic sustrate.

• Journal of Life Science
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• v.24 no.3
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• pp.323-328
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• 2014

MicroRNAs comprise a family of small noncoding RNAs that modulate physiological processes, including adipogenesis. MicroRNA-17 (miR-17) promotes adipocyte differentiation and enhances lipid accumulation. The transcriptional regulation of miR-17 during adipogenesis remains unknown. In this study, we investigated whether miR-17 is a target of peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$), which is a key regulator of adipogenesis. The levels of miR-17 and the expression of $PPAR{\gamma}$ increased after the induction of adipocyte differentiation. Three putative peroxisome proliferator response elements (PPREs) were identified in the miR-17 promoter region. Using chromatin immunoprecipitation and luciferase reporter assays, we observed the interaction of $PPAR{\gamma}$ with the miR-17 promoter. Mutagenesis experiments showed that the -677/-655 region of the miR-17 promoter could function as a PPRE site. These results suggest that $PPAR{\gamma}$ is essential for transcriptional activation of the miR-17 gene, thereby contributing to understanding the molecular mechanism of adipogenesis in adipocytes.

• Journal of Life Science
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• v.27 no.4
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• pp.482-499
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• 2017

Allergic diseases have increased over the past several decade worldwide including developing countries. Allergic inflammatory responses are caused by Th (T helper)2 immune responses, triggered by allergen ingestion by antigen presenting cells such as dendritic cells (DCs). Intestinal microorganisms control the metabolism and physiological functions of the host, contribute to early immune system maturation during the early life, and homeostasis and epithelial integrity during life. Bifidobacteria have strain-specific immunostimulatory properties in the Th1/Th2 balance, inhibit TSLP (thymic stromal lymphopoietin) and IgE expression, and promote Flg (Filaggrin) and FoxP3 (Treg) expression to alleviate allergies. In addition, unmethylated CpG motif ODN (oligodeoxynucleotides) is recognized by TLR (toll-like receptors)9 of B cells and plasmacytoid dendritic cells (pDCs) to induce innate and adaptive immune responses, while the butyrate produced by Clostridium butyricum activates the GPR (G-protein coupled receptors)109a signaling pathway to induce the expression of anti-inflammatory gene of pDCs, and directly stimulates the proliferation of thymically derived regulatory T (tTreg) cells through the activation of GPR43 or inhibits the activity of HADC (histone deacetylase) to differentiate naive $CD4^+$ T cells into pTreg cells through the histone H3 acetylation of Foxp3 gene intronic enhancer.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.1052-1056
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• 1997

When casein was hydrolyzed by trypsin, alcalase, neutrase, protamax, and S. aureus type V8, peptides $(100\;{\mu}g/mL)$ which were produced by trypsin and alcalase solubilized $6.42\;and\;2.37\;{\mu}g/mL)$ of added irons at pH 6, respectively, while peptides which were produced by other proteases solubilized less than $1\;{\mu}g/mL$. Peptides produced by trypsin and alcalase were fractionated to 10 fractions on a reverse phase column and each fraction was tested for its iron solubilizing ability at pH 6. Among peptides produced by trypsin, fraction 5 showed the highest iron solubilizing ability $(2.33\;{\mu}g/mL)$. In the case of alcalase, fraction 7 showed the highest iron solubilizing ability $(1.56\;{\mu}g/mL)$. To isolate iron binding peptides from peptides produced by trypsin and alcalase, immobilized iron affinity chromatography which irons were chelated to imino diacetic acids in chelating sepharose fast flow were utilized. Our results showed that immobilized iron affinity chromatography was an effective method to isolate iron binding peptides produced by either trypsin or alcalase from milk casein.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2001.06a
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• pp.8-8
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• 2001

초고속 증착은 짧은 시간에 박막 형성을 가능하게 하므로 window glass 코팅등의 대면적 코팅에 있어서 비용을 절감 시키고, 대량생산을 가능하게 만들기 때문에 관심이 집중되고 있다. 고속증착 공정으로는 high current arc, laser arc, hollow cathode discharge ion plating 그리고 마그네트론 스퍼터링법 등이 있다. 특별히 마그네트론 스퍼터링법은 3m이상의 넓이에 코팅을 할때 두께가 매우 균일하며, 증착율은 evaporation 공정에 비해 경제적, 기능적인 면에서 효율적이다. 그리고 증착된 박막은 매우 조밀하고 좋은 밀착력을 갖고 있으며, 고융점 금속을 포함하여 금속 합금 및 혼합물의 비율을 조정 및 금속 산화물, 질화물, 탄화물 등과 같은 금속의 증착도 stoichiometry를 조정하여 박막을 합성 시키는데 있어서 효과적이다. 이러한 초고속 증착을 만들기 위한 마그네트론 스퍼터링법의 요건은 마그네트론 원이 높은 타켓 power density를 가져야 하며, 타켓에서 효율적으로 플라즈마를 구속하여 스퍼터 되는 이온의 양을 최대화 시킬 수 있어 한다. 따라서 본 실험에서는 초고속 증착을 위해서 직경 50mm 타켓의 UBM magnetron원을 설계 제작하였다. 고밀도의 플라즈마를 형성시키기 위해서, Poisson simulation c code를 이용하여 자기장의 방향, 세기 및 밀도를 측정 하였고, 자기장 측정기(Gauss meter)를 이용하여 실제 자장을 측정 비교 분석하였다. 상기의 data를 바탕으로 여러 형상의 마그네트론원을 설계, 제작하였고. 마그네트론 원의 특성 분석을 위해 I-V 방전 특성을 평가하였고 substrate ion current density와 박막의 증착율을 측정하였다.duty-on 시간의 증가에 따라 $Cr_2N$ 상의 형성이 점점 많아져 80% duty-on 시간 경우에는 거의 CrN과 $Cr_2N$ 상이 공존하는 것으로 나타났다. 또한 duty-on 시간이 증가할수록 회절피크의 세기가 증가하여 결정화가 더 많이 진행되어짐을 알 수 있었다. 마찬가지로 바이어스 펄스이 주파수에 다른 결정성의 변화도 펄스의 주파수가 증가할수록 박막이 결정성이 좋아지고 $Cr_2N$ 상이 쉽게 형성되었다. 증착 진공도에 따른 결정성은 상대적으로 질소의 농도가 높은 낮은 진공도에서는 CrN 상이 주로 형성되었으며, 반대로 높은 진공도에서는 $Cr_2N$ 상이 많이 만들어졌다. 즉 $1.3{\times}10^{-2}Torr$의 증착 진공도에서는 CrN 상만이 보이는 반면 $9.0{\tiems}1-^{-2}Torr$ 진공도에서부터 $Cr_2N$ 상이 형성되기 시작하여 $5.0{\tiems}10^{-2}Torr$ 진공도에서는 두개의 상이 혼재되어 있음을 알 수 있었다. 박막의 내마모성을 조사한 결과 CrN 박막의 마찰 계수는 초기에 급격하게 증가한 후 0.5에서 0.6 사이의 값으로 큰 변화를 보이지 않았으며, $Cr_2N$ 박막도 비슷한 거동을 보였다.차 이, 목적의 차이, 그리고 환경의 의미의 차이에 따라 경관의 미학적 평가가 달라진 것으로 나타났다.corner$적 의도에 의한 경관구성의 일면을 확인할수 있지만 엄밀히 생각하여 보면 이러한 예의 경우도 최락의 총체적인 외형은 마찬가지로 $\ulcorner$순응$\lrcorner$