• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.117.3-118
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• 2003

We tested for the presence of double-stranded RNA (dsRNA) mycovirus in 827 Fusarium graminearum isolated from diseased barley and maize. dsRNA mycoviruses with various sizes were isolated. Of them, it was previously reported that dsRNA from DK2l isolate had pronounced morphological changes, including reduction in mycelial growth, increased to red pigmentation, reduced virulence and sporulation. (Chu et al., Appl. Environ. Microbiol. 2002). For better understanding of this hypovirulence associated with DK2l dsRNA virus, we determined the complete nucleotide sequence of dsRNA genome and named Fusarium hypovirus DK2l strain (Fhv-DK2l ). Genomic RNA of Fhv-DK2l was determined to be 6625 nucleotides in length excluding the poly (A) tail and contained three putative open reading frame. RNA-dependent RNA polymerase (RdRp) and helicase domain were expected in ORF A, 54 to 4709 nucleotide position. ORE B, 4752 to 5216 nucleotide position, and ORF C, 5475 to 6578 nucleotide position, were predicted to encode 16.7kDa and 41.3kDa protein respectively each. We could not detect any conserved domains from these two proteins. Phylogenetic analysis showed Fhv-DK2l was related to Cryphonectria hypovirus 3. Ten additional isolates were found that were infected with dsRNA mycoviruses. These mycoviruses contain 2 to 4 different segments of dsRNAs with the size range of approximately 1.7 to 10-kbp in length. The presence of dsRNAs isolates did not affect colony morphology and were transmissible through conidia and ascospore with incidence of 30-100％. These results indicate that there is genomic diversity of dsRNA mycoviruses that infect F. graminearum isolates and that impact of virus infection on host's morphology and virulence is determined by the interaction between dsRNAs and the fungal host, not by the mere presence of the dsRNAs

• 생태와환경
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• 제52권4호
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• pp.394-402
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• 2019

The Agrobacterium tumefaciens mediated gene transfer is widely used to generate genetic transformation of plants and transient assay of temporal exogenous gene expression. Syringe infiltration system into tobacco (Nicotiana benthamiana) leaves is a powerful tool for transient expression of target protein to study protein localization, protein-protein binding and protein production. However, the protocol and technical information of transient gene expression, especially double strand RNA (dsRNA), in tobacco using Agrobacterium is not well known. Recently, dsRNA is crucial for insecticidal effect on destructive agronomic pest such as Corn rootworm. In this study, we investigated the factor influencing the dsRNA expression efficiency of syringe agro-infiltration in tobacco. To search the best combination for dsRNA transient expression in tobacco, applied two Agrobacterium cell lines and three plant vector systems. The efficiency of dsRNA expression has estimated by real-time PCR and digital PCR. As a result, pHellsgate12 vector constructs showed the most effective accumulation of dsRNA in the cell. These results indicated that the efficiency of dsRNA expression was depending on the kind of vector rather than Agrobacterium cells. In summary, the optimized combination of transient dsRNA expression system in tobacco might be useful to in vivo dsRNA expression for functional study and risk assessment of dsRNA.

• The Plant Pathology Journal
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• 제27권3호
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• pp.285-290
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• 2011

Fusarium graminearum virus 2 (FgV2) infects Fusarium graminearum strain 98-8-60 and has at least five segments of double-stranded RNAs (dsRNAs), denoted as dsRNA-1 to dsRNA-5. In this study, the genome of FgV2 was sequenced and its phylogenetic relationship with other mycoviruses was analyzed. The lengths of FgV2 dsRNAs 1-5 ranged from 2414 to 3580 base pairs (bp). The 5' and 3' untranslated regions (UTRs) are highly conserved, and each dsRNA segment had 78-105 and 84-306 bp of 5' and 3' UTRs, respectively. Each dsRNA segment contained a single open reading frame (ORF). Computer analysis of dsRNA-1 revealed a putative open reading frame (ORF) that shows high sequence identity with an RNA-dependent RNA polymerase (RdRp) containing eight conserved motifs. dsRNAs 2-5 also each contain one putative ORF coding for products of unknown function. The sequences of FgV2 dsRNA-2 and dsRNA-3 have significant sequence identity with Magnaporthe oryzae chrysovirus 1 (MoCV1) dsRNA-3 and -4, respectively. When compared to other dsRNA mycoviruses in a phylogenetic analysis of the putative RdRp protein, FgV2 was found to form a distinct virus clade with Aspergillus mycovirus 1816 and MoCV1 in the family Chrysoviridae.

• 한국통신학회논문지
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• 제24권8A호
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• pp.1107-1114
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• 1999

본 논문에서는 대수정규 쉐도잉(shadowing)과 나카가미(Nakagami) 페이딩을 함께 받은 타 시스템의 동일 채널 간섭파가 불완전 전력제어 된 DS/CDMA 셀룰러 시스템의 용량에 미치는 영향을 분석하였다. 분석에는 먼저 간섭을 고려하지 않고 불완전 전력제어만을 해석한 Prasad와 Jansen의 결과와 비교하였으며, 대수정규-나카가미 페이딩을 받은 다중 간섭은 Schwartz와 Yeh가 제시한 방법을 적용하여 DS/CDMA 시스템에 미치는 영향을 오수신확률로 유도하였다. 유도한 오수신확률에 대해 불완전 전력제어, 페이딩 지수, 처리이득, 전력비, 간섭수, 음성화율 등을 파라미터로 하여 각각의 상황에서 DS/CDMA 시스템의 가입자 용량 감소를 분석하였다. 결과로부터 DS/CDMA 시스템의 용량은 전력제어 오차와 간섭파의 증가에 매우 민감하여 전력제어 오차가 클수록, 무선채널 환경의 페이딩이 심할수록, 또한 간섭파의 수가 증가할수록 감소하였다.

• 대한한방부인과학회지
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• 제24권2호
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• pp.13-32
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• 2011

Objectives: This study was performed to elucidate the effects of Danchisoyo-san (DS) on cell damage and gene expression in UVB-exposed dermal fibroblast. Methods: To demonstrate the inhibitory effects of DS on aging of the skin, we used human dermal fibroblast(F6) and UVB light(30 mJ/$cm^2$) was used to damage to dermal fibroblast. We measured the nitrite production, LDH release, and gene expression in UVB-irradiated dermal fibroblast to elucidate the actionmechanism of DS. Also, we evaluated the amount of increased PICP, TIMP-1 in dermal fibroblast. PICP, TIMP-1 concentration was measured using EIA kit, and gene expression (MMP-1, procollagen, c-fos, c-jun, NF-kB, Bcl-2, Bcl-xL, iNOS) were determined using real-time PCR. Results: 1. DS inhibited LDH-release, nitrite production in UVB-irradiated dermal fibroblast. 2. DS suppressed the gene expression of MMP-1 in UVB-irradiated dermal fibroblast. 3. DS increased the gene expression of procollagen in UVB-iradiated dermal fibroblast. 4. DS suppressed the gene expression of c-jun, c-fos, NF-kB, iNOS in UVBirradiated dermal fibroblast. 5. DS increased the gene expression of Bcl-2 in UVB-iradiated dermal fibroblast. 6. DS increased the cell proliferation of dermal fibroblast. Conclusions: From the results, we concluded DS increases the cell proliferation and collagen synthesis in dermal fibroblast. So we suggest that DS has the antiwrinkle effects.

• Molecules and Cells
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• 제46권4호
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• pp.219-230
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• 2023

Down syndrome (DS) is the most common autosomal aneuploidy caused by trisomy of chromosome 21. Previous studies demonstrated that DS affected mitochondrial functions, which may be associated with the abnormal development of the nervous system in patients with DS. Runt-related transcription factor 1 (RUNX1) is an encoding gene located on chromosome 21. It has been reported that RUNX1 may affect cell apoptosis via the mitochondrial pathway. The present study investigated whether RUNX1 plays a critical role in mitochondrial dysfunction in DS and explored the mechanism by which RUNX1 affects mitochondrial functions. Expression of RUNX1 was detected in induced pluripotent stem cells of patients with DS (DS-iPSCs) and normal iPSCs (N-iPSCs), and the mitochondrial functions were investigated in the current study. Subsequently, RUNX1 was overexpressed in N-iPSCs and inhibited in DS-iPSCs. The mitochondrial functions were investigated thoroughly, including reactive oxygen species levels, mitochondrial membrane potential, ATP content, and lysosomal activity. Finally, RNA-sequencing was used to explore the global expression pattern. It was observed that the expression levels of RUNX1 in DS-iPSCs were significantly higher than those in normal controls. Impaired mitochondrial functions were observed in DS-iPSCs. Of note, overexpression of RUNX1 in N-iPSCs resulted in mitochondrial dysfunction, while inhibition of RUNX1 expression could improve the mitochondrial function in DS-iPSCs. Global gene expression analysis indicated that overexpression of RUNX1 may promote the induction of apoptosis in DS-iPSCs by activating the PI3K/Akt signaling pathway. The present findings indicate that abnormal expression of RUNX1 may play a critical role in mitochondrial dysfunction in DS-iPSCs.

• Journal of Yeungnam Medical Science
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• 제33권1호
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• pp.8-12
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• 2016

Background: The decision to administer oral anticoagulation therapy depends on accurate assessment of stroke risk in patients with atrial fibrillation (AF). Various stroke risk stratification schemes have been developed to help inform clinical decision making. The CHADS2 and CHA2DS2-VASc scores have been used in estimating the risk of stroke in patients with AF. Recently R2CHA2DS2-VASc score was developed. The objective of the current study is to validate the usefulness of the R2CHA2DS2-VASc score and to compare the accuracy of the CHADS2, CHA2DS2-VASc, and R2CHA2DS2-VASc scores in predicting a patient's risk of stroke. Methods: Based on medical records, we conducted a retrospective study of patients hospitalized with AF from March 2011 to July 2013. A total of 448 AF patients were included in this study. The receiver operating characteristic (ROC) curve analysis in MedCalc was used for comparison with respective diagnostic values. Results: The patient characteristics showed male predominance (60.9%). Among the 448 AF patients, 131 (29.2%) patients had strokes during the study. A R2CHA2DS2-VASc score of more than 5 is the optimal cut-off value for prediction of stroke. A risk score of three, the area under the ROC curve (AUC) of R2CHA2DS2-VASc score (AUC 0.631; 95% confidence interval, 0.585-0.679) was the highest. A significant difference was observed between AUC for R2CHA2DS2-VASc, CHADS2, and CHA2DS2-VASc scores, but no meaningful difference between CHADS2 and CHA2DS2-VASc scores. Conclusion: We determined the usefulness of the R2CHA2DS2-VASc score, which showed better association with stroke than the CHADS2 and CHA2DS2-VASc scores.

• 전자공학회논문지S
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• 제36S권8호
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• pp.8-16
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• 1999

본 논문에서는 다중톤 방해신호가 존재하는 나카가미 페이디 전송로에서 BPSK 변조 및 동기검출을 이용하는 직접시퀀스/느린 주파수 도약(DS/SFH) 복합 확산대역 시스템의 성능을 분석한다. 나카가미 페이딩 전송로 모델은 페이딩 지수 m에 따라 다양한 전파환경을 표현할 수 있는 장점을 지니는데, m=1이면 레일레이 페이딩 분포를 나타내고, $1/2{\le}m{\le}1$이면 레일레이 페이딩보다 심한 페이딩을 나타낸다. m>1이면 라이시안 페이딩을 나타내고, m이 무한대로 감에 따라 페이딩이 없는 조건을 나타낸다. 본 논문은 이 모델을 근거로 복합 확산대역 시스템의 비트오율식을 유도하고, 여러가지 시스템 파라미터에 대하여 계산한 결과를 제시한다. 계산결과로부터 m이 증가함에 따라 페이딩의 영향은 줄어들고 이에 따라 더 좋은 성능을 나타내는 것을 알 수 있으며, 방해신호대 원하는 신호의 전력비(JSR)가 작은 경우에는 DS 확산대역 시스템의 성능이 DS/SFH 복합 확산대역 시스템보다 좋은 성능을 나타내지만, 방해신호대 원하는 신호의 전력비(JSR)가 큰 경우에는 DS/SFH 복합확산대역 시스템의 성능이 DS 확산대역 시스템 성능보다 더 우수하다. 결론적으로, 전체 대역폭을 일정하게 유지할 경우, 다중톤 방해신호가 존재하는 환경에서 DS/SFH 복합 확산대역 시스템의 성능이 DS확산대역 시스템의 성능보다 훨씬 더 우수함을 알 수 있다.

• 한국정보통신학회논문지
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• 제14권3호
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• pp.581-586
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• 2010

MC-DS-CDMA 전송 방식에서는 서로 직교성이 있는 여러 개의 부반송파들을 사용함으로서 주파수 다이버시티 효과를 얻을 수 있어 우수한 성능의 전송이 가능하다. 시변 페이딩 채널은 전송되는 MC-DS-CDMA 신호에 인접 부 반송파 간섭을 발생시켜 수신단에서 데이터 재생 시 비트오류율이 증가된다. 본 논문에서는 파일럿 심볼을 이용하여 채널을 추정하는 MC-DS-CDMA 시스템에서 선호가 시변 채널을 통하여 전송될 때의 시스템 성능을 분석한다. 이러한 다중 반송파 전송 방식에서는 채널 추정 에러, 송수산간 반송 주파수 편차 등에 의하여 시스템 성능이 열화 된다. 그러므로 위와 같은 영향들을 모두 고려하여 송선 신호가 다중 경로 페이딩 채널을 통하여 전송될 때의 데이터 비트오류율 성능을 분석한다.

• Journal of Welding and Joining
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• 제13권3호
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• pp.65-76
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• 1995

Weldability of DS100 and HY type high strength-toughness steel plates, tentatively produced as domestic production, was investigated. DS100 and DS130A had nearly same hardenability in HAZ in spite of its difference in Ceq. Based upon the y-groove test results, cold cracking susceptibility of DS130 was superior to that of DS100 because of its lower hydrogen level in weld metal. Solidification cracking tested by the Trans-Varestraint test was occured in all of the weld metals, and its susceptibility was high in the row of DS100, DS130A and DS130B. However, no liquation cracking and ductility-dip cracking tested by the Longi-Varestraint test with 6.0% augmented strain were detected in base metal and reheated weld metal. Toughness in the GMA welding joint was satisfied with the relative Mill Spec, even though welded joint of DS100 had relatively low impact energy especially at the weld metal.