• International Journal of Reliability and Applications
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• 제4권1호
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• pp.1-12
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• 2003

Many software reliability growth models (SRGM's) based on a nonhomogeneous Poisson process (NHPP) have been proposed by many researchers. Most of the SRGM's which have been proposed up to the present treat the event of software fault-detection in the testing and operational phases as a counting process. However, if the size of the software system is large, the number of software faults detected during the testing phase becomes large, and the change of the number of faults which are detected and removed through debugging activities becomes sufficiently small compared with the initial fault content at the beginning of the testing phase. Therefore, in such a situation, we can model the software fault-detection process as a stochastic process with a continuous state space. In this paper, we propose a new software reliability growth model describing the fault-detection process by applying a mathematical technique of stochastic differential equations of an Ito type. We also compare our model with the existing SRGM's in terms of goodness-of-fit for actual data sets.

• Journal of Ginseng Research
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• 제22권4호
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• pp.310-315
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• 1998

The effect of red ginseng saponins (total saponins, Rbl- and Rgl- fraction of saponins) on the induction of $\beta$-galactosidase in yeast, hccharomyces cereuisiae, was investigated to see that ginseng saponins would penetrate the cell membrane and have a function in a nucleus as steroid hormones do. To attain such a kind of purpose, a DNA fragment (685bp) containing GALI promoter was inserted into the sites of EcoRl and BamHl of polylinker region, upstream of lace gene of the plasmid YEp356 (7.966 Kb), and thus the resulting plasmid pGALl-lacZ is supposed to express $\beta$- galactosidase only in the presence of galactose. The plasmid pGALl -lacZ was introduced into yeast, Ky106 (a leu2 ura3 his3 trp 1 Iys2), and the growth of the transformed cells was much slower in the presence of galactose than glucose. The effects of saponins on the specific activity of P-galactosidase from transformed yeast cells were detected. No significant increase was observed in case of total saponins, but the Rbl- or Rgl- fraction of saponins gave much higher increase in the activity. Maximum increase was observed as 35% in 10-3% of Rbl and as 75% in 10-1% of Rgl. These data suggest that ginseng saponins might be able to enter the nucleus and stimulate transcription. However, further studies to find out the putative saponin receptor are needed to confirm this possibility. Key words : Red ginseng saponin, $\beta$-galactosidase induction, Saccharomyces cerevisiae.

• The Korean Journal of Ecology
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• 제19권1호
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• pp.21-29
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• 1996

Variation in triacylglycerols(TGs) and fatty acids in Fucus serratus was analyzed for a period of one year. TGs were more concentrated during the summer(2.8mg/g dw)and autumn(2.6mg/g dw) than during the spring (0,7mg/g dw)and winter (0.5mg/g dw). The dominant fatty acides in total liqid were palmitic acid ($C_{16:0}$, 24.1%), oleic acid (($C_{18:1}$, 22.4%) and arachidonic acid (($C_{20:4}$, 14.4%) but the dominant ones in TG were $C_{16:0}$(22.8%), $C_{18:1}$(36.4%) and $C_{18:2}$(linoleic acid, 16.4%). The levels of $C_16$ fatty acids were high in winter while $C_18$ in summer and autumn. The polyunsaturated fatty acids (UFAs) were more abundant in the $C_20$ series, while the UFAs of the $C_16$ were low. Especially, the amount of arachidonic acid ($C_{20:4}$, 14.4% of total fatty acids (TFA) was more abundant than that of eicosapentaenoic acid ($C_{20:5}$, 10.4% of TFA). The amount of $C_{20:4}$ and $C_{20:5}$,in TG was 9.2% and 4.8%, respectively. These UFAs in total lipid were thus higher than TG. Therefore, the synthesis of TG and fatty acid was stimulated by the alternation of emersion and submersion of thalli from sea water and eco-physiological conditions during summer: high temperature and light, and low concentration of nitrogen.

• 농촌계획
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• 제11권4호
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• pp.75-91
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• 2005

This study designs an integrated data architecture to systematically manage the agricultural statistics database. Managing the agricultural statistics is important since it provides data for policies and decision making for agribusinesses. Ministry of Agriculture and the National Statistical Office collect the basic agricultural statistic data which provides the basis of logical decision making and agricultural policies. However, the agricultural statistic data has not well been used. The data has not been consistently collected nor managed. The raw data has not been organized nor processed to meet various demands. The needs has been arisen for a consistent agricultural statistics system to increase the relevance, accessibility, and efficiency of data for various users. There are massive amount of data accumulated over a long time period. Introducing the new system and reorganizing the data will bear large risks. A systematic method is required to reduce the risks in planing, building, and maintaining the database without hindering administration. This study provides a design of the agricultural statistics system architecture based on the user requirement analysis (URA) and similar systems abroad. We have also build a prototype to check the implementability of the system design.

• Journal of Microbiology and Biotechnology
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• 제8권6호
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• pp.650-655
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• 1998

The chromosomal DNA fragment from Phaffia rhodozyma CBS 6938 which is able to autonomously replicate in the yeast Saccharomyces cerevisiae was cloned on an integrative URA3 plasmid. Its minimal fragment exhibiting autonomously replicating activiy in the S. cerevisiae gave a higher frequency transformation efficiency than that found for centromere-based plasmid, and enabled extrachromosoma1ly stable transmission of the plasmids in one copy per yeast cell under non-selective culture condition. The 836-bp DNA element lacked an ORF and did not contain any acceptable match to an ARS core consensus. Sequence analysis, however, displayed a cluster of three hairpin-Ioop-sequences with individual $\triangle {G_{25}}^{\circ}C$ free energy value of -10.0, -17.5, and -17.0 kcal. $mor^{-l}$as well as a 9-bp sequence with two base pair mismatches to the S. cerevisiae/E. coli gyrase-binding site. This 836-bp sequence also included one 7-bp sequence analogous to the core consensus of centromeric DNA element III (CDEIII) of S. cerevisiae, but CDEIII-like 7 bp sequence alone did not give a replicative function in this yeast.

• 건축역사연구
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• 제23권6호
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• pp.27-37
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• 2014

Early 20th century Singapore was faced with the problem of overcrowding. The attendant problems of a rapid increase in population density, namely the lack of proper housing and sanitation, resulted in the issue of an appropriate residential environment emerging as an important task in urban planning. It was necessary to construct housing estates in order to solve this issue. At that time, the British colonial government attempted to transplant modern technology into the construction process of a residential complex system. However, Singapore's climate and traditional lifestyle made it impossible to apply the British modern system in a straightforward manner, and in the process, a number of transformations emerged. With a specific focus on the Tiong Bahru estate, one of Singapore's representative public housing projects, from the 1930s through the 1950s, this study intends to look at the way in which such residential estates were assimilated into local surroundings, and the effect of the transplantation of British concepts of modern housing theory. Therefore, the study is divided into an examination of the estate both before and after the turning point of World War II. This study confirms that the difference between the pre-war and post-war planning strategies for the Tiong Bahru estate were made according to the concept of 'open space.'

• Asian Pacific Journal of Cancer Prevention
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• 제16권13호
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• pp.5433-5438
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• 2015

Background: Systemic chemotherapy for patients with metastatic gastric cancer (MGC) is generally palliative, although some patients experience long-term survival after treatment. Thus, we identified clinical characteristics that are associated with long-term survival of patients with MGC after palliative chemotherapy. Materials and Methods: We retrospectively reviewed 514 MGC patients who received systemic chemotherapy at our institution from 2001 to 2008. To identify clinical predictors of survival beyond 2 years, multivariate logistic regression analyses were performed, and 5-year survival rates were estimated among MGC patients following chemotherapy. Results: Among 514 patients, 96 (19%) and 16 (3%) survived beyond 2 and 5 years, respectively, and performance status of 0 or 1 (odds ratio [OR]=3.39; p=0.01), previous gastrectomy (OR=1.86; p=0.01), single metastatic site (OR=1.80; p=0.03), and normal alkaline phosphatase levels (OR=2.81; p<0.01) were identified as independent predictors of long-term survival. Of the 16 5-year survivors, six were alive at the end of the study and showed no evidence of disease despite cessation of chemotherapy. Conclusions: The present data demonstrate distinct clinical characteristics that are associated with long-term survival of MGC patients, and indicated that palliative chemotherapy can be curative in highly selected patients.

• 미생물학회지
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• 제46권4호
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• pp.401-404
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• 2010

출아효모 Saccharomyces cerevisiae에서 RNA-binding 단백질인 Tho1은 mRNA가 전사되는 동안 초기 mRNA에 결합하여 mRNP 생성과 성숙한 mRNA의 핵에서 세포질로의 방출에 관여하는 것으로 여겨진다. 분열효모 Schizosaccharomyces pombe에서도 Tho1과 유사한 단백질을 암호화하는 유전자(spTho1로 명명)를 찾아 그 특성을 조사하였다. 이배체 S.pombe 균주에 하나의 spTho1 유전자만을 결실시킨 후 4분체분석을 수행한 결과, 이 유전자는 생장에 반드시 필요하지 않았다. 또한 spTho1 결실 돌연변이는 mRNA의 핵에서 세포질로의 방출도 정상적으로 보였다. 그러나 티아민에 의해 발현이 조절되는 강력한 프로모터를 이용하여 spTho1를 과발현시키면, 세포의 생장이 억제되었으며 $poly(A)^+$ RNA가 핵 안에 축적되었다. 이와 같은 결과들은 spTho1 유전자가 필수적이지는 않지만 mRNA의 핵에서 세포질로의 방출에 관여하고 있음을 시사한다.

• 미생물학회지
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• 제50권3호
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• pp.249-253
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• 2014

THOC7/Mft1는 mRNA가 전사되는 동안 mRNP의 포장과 mRNA 방출에 관여하는 진화적으로 잘 보존된 THO 복합체의 구성인자이다. 분열효모 Schizosaccharomyces pombe에서 THOC7/Mft1의 이종상동체(spThoc7)가 합성치사 돌연변이체 SLRsm1의 생장 결함을 부분적으로 상보하는 것으로 선별되었다. 이배체 S. pombe 균주에 하나의 spthoc7 유전자만을 결실시킨 후 4분체 분석을 수행한 결과, 이 유전자는 생장에 필수적이지 않았다. 하지만, ${\Delta}thoc7$ 결실돌연변이는 생장과 mRNA의 핵에서 세포질로의 방출에 약간의 결함을 보였다. 기능을 하는 spThoc7-GFP단백질은 주로 핵 안에 존재하였다. 이와 같은 결과들은 spThoc7도 mRNA 방출에 관여하고 있음을 시사한다.

• 미생물학회지
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• 제44권1호
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• pp.80-84
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• 2008

mRNA의 핵에서 세포질로의 이동에 중요한 역할을 하는 발아효모 Saccharomyces cerevisiae의 DEAD-box RNA helicase인 DBP5 유전자와 유사한 분열효모 Schizosaccharomyces pombe의 유전자(spDbp5로 명명)의 결실돌연변이주(knockout mutant)를 제조하여 그 특성을 조사하였다. 이배체인 S. pombe 균주에 하나의 spDbp5 유전자만을 결실시킨 후 4분체분석(tetrad analysis)을 수행한 결과, 이 유전자가 결실된 반수체 균주는 생장하지 못했다. mRNA의 핵에서 세포질로의 이동에 있어서 spDbp5의 역할을 알아보기 위해, spDbp5의 발현이 티아민(thiamin)에 의해 억제되는 균주를 제작하여 in situ hybridization을 통해 세포 내의 $poly(A)^+$ RNA 분포를 살펴보았다. spDbp5 유전자의 발현이 억제되면, $poly(A)^+$ RNA가 핵 안에 축적되고세포질에서는 줄어들었다. 이와 같은 결과들은 spDbp5 유전자 역시 mRNA의 핵에서 세포질로의 이동에 매우 중요한 역할을 담당하고 있음을 시사한다.