• Molecules and Cells
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• 제37권8호
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• pp.620-627
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• 2014

We have previously shown that microRNAs (miRNAs) miR-760, miR-186, miR-337-3p, and miR-216b stimulate premature senescence through protein kinase CK2 (CK2) downregulation in human colon cancer cells. Here, we examined whether these four miRNAs are involved in the replicative senescence of human lung fibroblast IMR-90 cells. miR-760 and miR-186 were significantly upregulated in replicatively senescent IMR-90 cells, and their joint action with both miR-337-3p and miR-216b was necessary for efficient downregulation of the ${\alpha}$ subunit of CK2 ($CK2{\alpha}$) in IMR-90 cells. A mutation in any of the four miRNA-binding sequences within the $CK2{\alpha}3^{\prime}$-untranslated region (UTR) indicated that all four miRNAs should simultaneously bind to the target sites for $CK2{\alpha}$ downregulation. The four miRNAs increased senescence-associated ${\beta}$-galactosidase (SA-${\beta}$-gal) staining, p53 and $p21^{Cip1/WAF1}$ expression, and reactive oxygen species (ROS) production in proliferating IMR-90 cells. $CK2{\alpha}$ overexpression almost abolished this event. Taken together, the present results suggest that the upregulation of miR-760 and miR-186 is associated with replicative senescence in human lung fibroblast cells, and their cooperative action with miR-337-3p and miR-216b may induce replicative senescence through $CK2{\alpha}$ downregulation-dependent ROS generation.

• Biomolecules & Therapeutics
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• 제25권5호
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• pp.490-496
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• 2017

Imatinib resistance has become a major clinical problem for chronic myeloid leukemia. The aim of the present study was to investigate the involvement of MEG3, a lncRNA, in imatinib resistance and demonstrate its underlying mechanisms. RNAs were extracted from CML patients' peripheral blood cells and human leukemic K562 cells, and the expression of MEG3 was measured by RT-qPCR. Cell proliferation and cell apoptosis were evaluated. Western blotting was used to measure the protein expression of several multidrug resistant transporters. Luciferase reporter assay was performed to determine the binding between MEG3 and miR-21. Our results showed that MEG3 was significantly decreased in imatinib-resistant CML patients and imatinib-resistant K562 cells. Overexpression of MEG3 in imatinib-resistant K562 cells markedly decreased cell proliferation, increased cell apoptosis, reversed imatinib resistance, and reduced the expression of MRP1, MDR1, and ABCG2. Interestingly, MEG3 binds to miR-21. MEG3 and miR-21 were negatively correlated in CML patients. In addition, miR-21 mimics reversed the phenotype of MEG3-overexpression in imatinib-resistant K562 cells. Taken together, MEG3 is involved in imatinib resistance in CML and possibly contributes to imatinib resistance through regulating miR-21, and subsequent cell proliferation, apoptosis and expression of multidrug resistant transporters.

• 한국콘텐츠학회논문지
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• 제17권4호
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• pp.468-477
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• 2017

본 연구의 목적은 간호대학생을 대상으로 학습만족도에 영향을 주는 요인을 파악하여 새로운 학습법을 도입할 때 대상자의 학습만족도를 높이기 위해 고려해야 하는 요소에 대한 기초 자료를 제공하기 위함이다. 본 연구에서는 자기주도학습 준비도, 교수-학생 상호작용, 핵심역량, 스트레스와 학습동기가 학습만족도에 미치는 영향을 분석하였다. 이러한 변수를 측정하기 위하여 자기주도적 학습준비도 검사, 교사-학생관계척도, 대학생 핵심역량, 대학차원의 스트레스 측정도구, 학습동기 측정표, 학습만족도 측정도구를 수정 보완한 도구를 사용하였다. 연구대상은 S시에 위치한 E대학교 간호대학생 2, 3학년을 대상으로 하였으며, 총 132명의 자료가 최종 분석에 포함되었다. 본 연구의 결과 학습만족도는 자기주도학습 준비도(r= .21, p= .018), 교수-학생 상호작용(r= .39, p<.001), 핵심역량(r= .21, p= .014), 학습동기(r= .75, p<.001)와 양의 상관관계를 보였다. 또한 학습동기는 자기주도학습 준비도(r= .24, p= .005), 교수-학생 상호작용(r= .38, p<.001), 핵심역량(r= .21, p= .018)과 양의 상관관계를 보였다. 학습만족도에 영향을 미치는 요인은 학습동기와 교수-학생 상호작용이었으며, 이 2개의 변수로 구축된 회귀모형의 학습만족도에 대한 설명력은 59.7%였다. 따라서 본 연구의 결과 학습만족도를 높이기 위해서는 학습동기를 고취시키고 교수-학생 상호작용이 효율적으로 일어날 수 있도록 하는 중재가 필요하겠다.

• 한국발생생물학회지:발생과생식
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• 제18권1호
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• pp.33-41
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• 2014

We investigated the process of yolk absorption in Korean rose bitterling, Rhodeus uyekii, and determined the changes in its morphometric characteristics. The R. uyekii from 1 days post hatching (DPH) to 21 DPH, the eye diameter (ED) was 5.4 at 5 DPH. Thereafter, the ED/total length (TL) ratio increased to 10.7 at 21 DPH (p<0.05). The yolk length (YL) decreased from 95.4 to 1.1 by 21 DPH, and this rate of decrease was greater than that for any other dimension (p<0.05). 12 morphometric dimensions/TL for the R. uyekii were measured at each sampling day from 21 DPH to 170 DPH. At just hatching, the average TL and BW were $6.1{\pm}0.09mm$ and $4.9{\pm}0.07mg$, respectively. At 53 DPH, the average TL was $12.9{\pm}0.28mm$ and the average BW was $14.7{\pm}0.72mg$; the total length growth equation was $TL=5.507e^{0.038t}$ ($R^2=0.916$). Further, the body weight growth equation was $BW=3.3647e^{0.0296t}$ ($R^2=0.9354$). The dimensions with regard to body depth showed the greatest growth rates in the external characteristics of the fish (p<0.05). The patterns of the morphometric characteristics measured in this study can be classified in three ways. The patterns were shown to be increased (y=0.0992x+12.07, $R^2=0.8333$), decreased (y=-0.0569x+42.029, $R^2=0.8395$) or maintained (y=0.005x+18.263, $R^2=0.3678$) from 21 DPH to 170. These results will provide useful indices for the successful rearing of the R. uyekii.

• 전기학회논문지
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• 제67권9호
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• pp.1141-1145
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• 2018

Generally, in nuclear plants, distance relay (21R) has adapting to protect and to operate main protective of transmission lines and backup protective of main generator. Operation of 21R was required and based on exactly accurate calculation and criteria. But presently method of 21R setting has applied according to protection devices operation guide of KPX, excepting IEEE and ISA standards, which have a difference review directions, consider parameters and devices, also consideration factors were affected to relay operations by uncertain guides. therefore this paper proposed new protection relay setting method and unvague criteria from IEEE 741 and ANSI/ISA 67.04.01, and reviewed a different results through numerical calculation results for methods and criteria including previous and established 21r setting by IEEE, ANSI/ISA Technical standards.

• 문화기술의 융합
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• 제4권1호
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• pp.41-50
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• 2018

본 연구는 대학생의 스마트폰 중독과 스트레스, 회복탄력성과의 관계를 확인하고, 스마트폰 중독에 미치는 영향을 파악하기 위해 실시하였다. 연구대상자는 전라남도 소재 4년제 대학생 241명이다. 자료수집은 2017년 7월 6일부터 8월 31일까지 실시하였다. 연구결과, 대상자의 스마트폰 중독과 스트레스(r=.37, P<.001)는 양의 상관관계가 있었으며, 회복탄력성(r=.-25, p<.001)과는 음의 상관관계가 있었다. 대상자의 스트레스 중 당면과제(r=.40, p<.001)와 대인관계(r=.25, p<.001)는 양의 상관관계가 있었으며, 회복탄력성 중 자기조절능력(r=-.32, p<.001)과 대인관계능력(r=-.21, p=.001)은 음의 상관관계가 있었다. 스마트폰 중독에 영향을 미치는 변수는 학업문제(${\beta}=.15$, p=.047)와 자기조절능력(${\beta}=-.21$, p=.007)으로 총 설명력($R^2$)은 22.1%였다. 따라서 대학생의 스마트폰 중독을 예방하고 관리하기 위한 체계적인 교과외 프로그램의 개발이 필요할 것으로 사료된다.

• Biomolecules & Therapeutics
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• 제23권2호
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• pp.141-148
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• 2015

Epithelial mesenchymal transition (EMT) is the first step in metastasis and implicated in the phenotype of cancer stem cells. Therefore, understanding and controlling EMT, are essential to the prevention and cure of metastasis. In the present study, we examined, by Western blot, reverse transcription polymerase chain reaction (RT-PCR), and confocal microscopy, the effects of cardamonin (CDN) on transforming growth factor-${\beta}1$ (TGF-${\beta}1$)-induced EMT of A549 lung adenocarcinoma cell lines. TGF-${\beta}1$ induced expression of N-cadherin and decreased expression of E-cadherin. CDN suppressed N-cadherin expression and restored E-cadherin expression. Further, TGF-${\beta}1$ induced migration and invasion of A549 cancer cells, which was suppressed by CDN. TGF-${\beta}1$ induced c-Jun N-terminal kinase (JNK) activation during EMT, but CDN blocked it. Protein serine/threonine phosphatase 2A (PP2A) expression in A549 cancer cells was reduced by TGF-${\beta}1$ but CDN restored it. The overall data suggested that CDN suppresses TGF-${\beta}1$-induced EMT via PP2A restoration, making it a potential new drug candidate that controls metastasis.

• Journal of Information Technology Applications and Management
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• 제21권4_spc호
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• pp.345-359
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• 2014

Technological, policy and economic factors are both important variables in maximizing the results of a national R&D program and key indicators in evaluating an R&D program's eligibility for financial support. Economic analysis, in particular, is used when selecting R&D programs, setting priorities, and estimating economic effects. This paper examines a series of methodological issues related to the economic analysis of national R&D programs within the framework of the current preliminary feasibility evaluation system, and proposes alternative approaches to each of the issues discussed. The issues include the definition of R&D valuation and establishment of valuation factors; estimation of sales attributable to R&D investment; assessment of the total economic value of R&D as intellectual assets; estimation of R&D benefits and assumption of related to sales; and the application of discount rates based on the weighted average cost of capital. Finally, this study presents directions for future research on analytical procedures and methods of improving the reliability of the results of economic analysis within the national technology planning system.

• 대한수학회논문집
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• 제21권1호
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• pp.1-9
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• 2006

A ring R is called (left principally) quasi-Baer if the left annihilator of every (principal) left ideal of R is generated by an idempotent. Let R be a ring, G be an ordered monoid acting on R by $\beta$ and R be G-compatible. It is shown that R is (left principally) quasi-Baer if and only if skew monoid ring $R_{\beta}[G]$ is (left principally) quasi-Baer. If G is an abelian monoid, then R is (left principally) quasi-Baer if and only if the Cohn-Jordan extension $A(R,\;\beta)$ is (left principally) quasi-Baer if and only if left Ore quotient ring $G^{-1}R_{\beta}[G]$ is (left principally) quasi-Baer.

• Genomics & Informatics
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• 제2권4호
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• pp.174-179
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• 2004

We developed various plasmid cloning vectors that are useful in the construction of genomic and shotgun libraries. Two medium copy vectors, pCUGlblu21 (pCb21) and pAGlblu21 (pAb21), which are resistant to kanamycin ($Km^R$) and chloramphenicol ($Cam^R$), respectively, are useful for cloning DNA inserts ranging from 5kb to 15kb. Two high copy vectors, pCUGlblu31 (pCb31) and pAGlblu31 (pAb31), containing $Km^R$ and $Cam^R$, respectively, are useful for DNA inserts less than 5kb. These vectors are well adapted for large-scale genome sequencing projects by providing choice of copy number and selectable marker. The small vector size is another advantage of these vectors. All vectors contain lacZa including multicloning sites that originated from pBluscriptllsk- for easy cloning and sequencing. Two medium copy vectors contain unique and rare cutting Swal (ATTTAAAT) restriction enzyme sites for easy determination of insert size. We developed two combined vectors, pC21A31 and pC31A21, which are combinations of (pCb21 + pAb31) and (pCb31 + pAb21), respectively. These two vectors provide four choices of vectors such as $Km^R$ and medium, $Cam^R$ and high, $Cam^R$ and medium, and $Km^R$ and high copy vectors by restriction enzyme cutting, dephosphorylation, and gel purification. These vectors were successfully applied to high throughput shotgun sequencing of rice, tomato, and brassica BAC clones. With an example of extremely biased hydro sheared 3 kb shotgun library of a tomato BAC clone, which is originated from cytogenetically defined peri-centromeric region, we suggest the utility of an additional 10 kb library for sequence assembly of the difficult-to-assemble BAC clone.