• Journal of Korean Institute of Industrial Engineers
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• v.28 no.4
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• pp.390-396
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• 2002

We present a meaningful interpretation of the equations for the steady-state queue length distribution of the GI/GI/c/K queue so that the equations are better understood and become more applicable. As a byproduct, we present an exact expression of the mean queue waiting time for the M/GI/c queue.

• Journal of applied mathematics & informatics
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• v.31 no.1_2
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• pp.311-325
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• 2013

The effects of the moments of the interarrival time and service time on the system performance measures such as blocking probability, mean and standard deviation of the number of customers in service facility and orbit are numerically investigated. The results reveal the performance measures are more sensitive with respect to the interarrival time than the service time. Approximation for $GI/G/c$ retrial queues using $PH/PH/c$ retrial queue is presented.

• Journal of Applied Biological Chemistry
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• v.57 no.3
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• pp.247-250
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• 2014

A lipid-soluble extract in ginseng marc was prepared by n-hexane extraction to evaluate its antioxidant and anticancer potential. A hexane extract of ginseng marc (HEGM) possessed a 2,2-diphenyl-1-picryl-hydrazyl free radical scavenging activity which was related to the amount of total phenolics. Also, HEGM showed a potent inhibitory activity on human non-small cell lung cancer (A549, $GI_{50}=34.0{\mu}g/mL$) and colon cancer (SNU-C4, $GI_{50}=45.2{\mu}g/mL$) cells proliferation in vitro in a concentration-dependent manner as did the hexane extract of ginseng with $GI_{50}$ values of $20.0{\mu}g/mL$ in A549 and $37.0{\mu}g/mL$ in SNU-C4. These results imply that HEGM can be utilized as an antioxidant and anticancer substance.

• Journal of the Korean Operations Research and Management Science Society
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• v.29 no.3
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• pp.1-7
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• 2004

We demonstrate in this paper that the level crossing technique can be applied to such a system that not only the state vector is two-dimensional but Its two components are heterogeneous. As an example system, we use the GI-G/c/K queue whose state vector consists of the number of customers in the system and the total unfinished work.

• Journal of Life Science
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• v.18 no.8
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• pp.1132-1139
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• 2008

A CpG island is a short stretch of DNA in which the frequency of the CG dinucleotide is higher than other regions. CpG islands are present in the promoters and exonic regions of approximately $30{\sim}60$% of mammalian genes so they are useful markers for genes in organisms containing 5-methylcytosine in their genomes. Recent evidence supports the notion that the hypermethylation of CpG island, by silencing tumor suppressor genes, plays a major causal role in cancer, which has been described in almost every tumor types. In this respect, CpG island search by computational methods is very helpful for cancer research and computational promoter and gene predictions. I therefore developed a window program (called CpGi) on the basis of CpG island criteria defined by D. Takai and P. A. Jones. The program 'CpGi' was implemented in Visual C++ 6.0 and can determine the locations of CpG islands using diverse parameters (%GC, Obs (CpG)/Exp (CpG), window size, step size, gap value, # of CpG, length) specified by user. The analysis result of CpGi provides a graphical map of CpG islands and G+C% plot, where more detailed information on CpG island can be obtained through pop-up window. Two human contigs, i.e. AP00524 (from chromosome 22) and NT_029490.3 (from chromosome 21), were used to compare the performance of CpGi and two other public programs for the accuracy of search results. The two other programs used in the performance comparison are Emboss-CpGPlot and CpG Island Searcher that are web-based public CpG island search programs. The comparison result showed that CpGi is on a level with or outperforms Emboss-CpGPlot and CpG Island Searcher. Having a simple and easy-to-use user interface, CpGi would be a very useful tool for genome analysis and CpG island research. To obtain a copy of CpGi for academic use only, contact corresponding author.

• Journal of the Korean Operations Research and Management Science Society
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• v.40 no.1
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• pp.1-4
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• 2015

This paper presents a heuristic approach to derive the Laplace-Stieltjes transform (LST) and the probability generating function (PGF) of the waiting time distributions of a continuous- and a discrete-time GI/G/1 queue, respectively. This is a new idea to derive the well-known results, the waiting time distribution of GI/G/1 queue, in a different way.

• Journal of Applied Biological Chemistry
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• v.59 no.2
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• pp.133-136
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• 2016

An acetone extract in the cortex of Ulmus pumila L. was prepared to evaluate its anti-oxidative and anti-proliferative activities. The free radical scavenging activity ($EC_{50}=36.7{\mu}g/mL$) and reducing power ($EC_{50}=53.2{\mu}g/mL$) proportionally increased according to the extract concentration. The acetone extract possessed a potent anti-proliferative activity against human non-small cell lung cancer (A549, $GI_{50}=74.3{\mu}g/mL$) and human colon cancer (SNU-C4, $GI_{50}=92.8{\mu}g/mL$) cells in a dose-dependent manner, but was less effective with human normal cells (L132, human embryonic lung epithelial cell).

• Journal of the Korean Society of Tobacco Science
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• v.37 no.1
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• pp.25-33
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• 2015

Genome walking is a par ticular application for identifying sequences of unknown genomic regions adjacent to a known region. Many genome walking methods based on polymerase chain reaction (PCR) are available. Even if earlier techniques suffer from low reproducibility, inefficiency, and non-specificity, improved strategies have been developed. In this study, we present an alternative strategy: the genomic DNA is digested with restriction enzymes. After cytosine overhangs at 5' ends, the fragments are ligated to linker adaptor s had guanine overhang at 3' ends. Then nested PCR is performed. The improvements in this strategy focus on two points. The first is the C tailing method using Pfu polymerase instead of the A tailing method based on nontemplate-dependent terminal transferase activity of Taq polymerase. Therefore unintended modification of target DNA can be prevented without A tailing error. The second point is the use of C/G-specific ligation had advantage in the ligation efficiency compared with A/T-specific ligation. Therefore, the C-G linker PCR method increases ligation efficiency between digested genomic DNA and adaptor DNA. As a result, the quantity of target DNA to amplify by PCR is enriched. We successfully used G-C linker PCR to retrieve flanking regions bordering the phophinothricin resistance gene in genetically modified tobacco (GMO).

• Biomedical Science Letters
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• v.10 no.4
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• pp.407-413
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• 2004

Heterotrimeric GTP binding proteins (G proteins) transduce signals of a variety of hormones and neurotransmitters. Go is one of the most abundant G proteins in the brain and classified as the Gi/Go family due to their sequence homology to Gi proteins. While the Gi proteins inhibit adenylyl cyclase and decrease the intracellular cAMP concentration, the functions of Go is not clearly understood despite their sequence homology to Gi. The promeylocytic leukemia zinc finger protein (PLZF) is a DNA binding transcription factor and is expressed highly in central nervous system (CNS). Several studies reported that PLZF may be involved in regulation segmentation/differentiation during CNS development. Here, I report that the alpha subunit of Go (Go ) interacts with PLZF. The interaction between Goa and PLZF was verified by using GST pulldown assay and co-immunoprecipitation. Our findings indicate that Goa could modulate gene expression via interaction with PLZF during neuronal or brain development.

• Korean Journal of Optics and Photonics
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• v.6 no.1
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• pp.45-49
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• 1995

시간 상관 단일 광자 계수법을 사용하여 PVP/C/sub 2/H/sub 5/OH와 PEG/H/sub 2/O 혼합 용매에 위치한 rhodemine 6G 분자의 회전 재배열 시간을 측정하였다. 주어진 온도에서 혼합비를 변화시키면서 측정한 결과, PEG/H/sub 2/O와 PVP/C/sub2/H/sub 5/OH에서 각각 회전 이완 시간이 혼합액의 점성도에 선형적으로 비례하지 않는 것으로 관측되었다. 고분자 주의에 cluster가 형성된다는 관점에서 혼합비에 따른 회전 이완 시간의 변화를 설명하였다.