• Journal of the Korean Society for Precision Engineering
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• v.17 no.1
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• pp.145-152
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• 2000

X-ray diffraction method detects change of crystal lattice distance under material surface using diffraction angle 2$\theta$. This technique can be applied to the behavior on slip band and micro crack due to material degradation. The relation between half-value breadth and number of cycle has three stages which constitute rapid decrease in initial number of cycles, slight decrease in middle number of cycles and rapid decrease in final number of cycles. The ratio of half-value breadth takes a constant value on B/B$_{0}$-N diagram with loading condition except early part of fatigue life. The ratio of half-value breadth B/B$_{0}$ with respect to number of cycle to failure N$_{f}$ has linear behavior on B/B$_{0}$-log N$_{f}$ diagram. Therefore, in this paper the estimation of fatigue life by average gradient method has much less estimated mean error than the estimation of fatigue life by log B/B$_{0}$-log N/N$_{f}$ relation.elation.ation.

• International Journal of Precision Engineering and Manufacturing
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• v.3 no.2
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• pp.78-86
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• 2002

In general, X-ray diffraction method detects the changes of crystal lattice under material surface using the angle of diffraction 2$\theta$. This technique which deals with in the presented paper can be applied to a behavior on the slipped band or the micro crack cause to material degradation. The relation between half-value breadth and cycle numbers shows three stages, which consist of rapid decrease in the initial cycle, slight decrease in the middle cycle, and then rapid decrease in the final cycle. The ratio of half-value breadth has a constant value on B/B$\_$0/ - N diagram under the loading condition except early part of fatigue life. The ratio of half-value breadth B/B$\_$0/ - log N$\_$f/ with respect to number of cycle to failure N$\_$f/ has linear behavior on B/B$\_$0/ - log N$\_$f/ diagram. Therefore, the evaluation of fatigue life by the average gradient has much less mean error than the estimation of fatigue life by log B/B$\_$0/ - log N/N$\_$f/ relation.

• Journal of Applied Reliability
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• v.14 no.4
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• pp.262-266
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• 2014

In this paper, we consider the problem of determining the confidence level in zero-failure reliability sampling plans when the life distribution is Weibull distribution with a shape parameter m and a scale parameter ${\eta}$. We introduce zero-failure reliability sampling plans for Weibull distribution and investigate some characteristics of zero-failure reliability sampling plans. Finally, We propose new guideline for determining the confidence level in zero-failure reliability sampling plans for assuring $B_x-life$.

• Journal of Applied Biological Chemistry
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• v.59 no.1
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• pp.25-29
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• 2016

Hepatitis B virus infection can cause hepatic fibrosis leading to cirrhosis and hepatocellular carcinoma. However the mechanism remains poorly understood. In this study, we found that Hepatitis B virus X-protein (HBx) increases vimentin, fibronectin, slug, snail and NOX4 expression. Because NOX4-mediated reactive oxygen species can increase slug and snail, which can induce fibrosis, HBx may be a key regulator of hepatic fibrosis development via NOX4 induction.

• BMB Reports
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• v.54 no.3
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• pp.176-181
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• 2021

Bcl-x, a member of the Bcl-2 family, plays a key role in apoptosis. Alternative splicing of Bcl-x pre-mRNA through alternative 5' splice-site selection produces an anti-apoptotic mRNA isoform that includes exon 2b and a pro-apoptotic Bcl-x mRNA isoform that excludes exon 2b. Here we used Bcl-x minigene and identified SRSF2 and SRSF6 as two regulatory factors of 5' splice-site selection of Bcl-x pre-mRNA. We selected binding clusters closer to 5' splice-sites from multiple potential binding sites of SRSF2 and SRSF6 to perform loss of functions analysis through site-directed mutagenesis. Our results demonstrated that these mutations did not abolish regulatory functions of SRSF2 or SRSF6, indicating that a single binding motif or a cluster was not a functional target of these proteins in Bcl-x pre-mRNA splicing. Random deletion mutagenesis did not disrupt the role of SRSF2 and SRSF6. Importantly, mutagenesis of 5' splice-site to a conserved or a weaker score demonstrated that the weaker strength of the target 5' splice-site or higher strength of the other 5' splice-site strength limited the role of SRSF2 and SRSF6 in 5' splice-site activation.

• Proceedings of the Korean Society of Crop Science Conference
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• 2004.10a
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• pp.94-95
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• 2004

• Molecules and Cells
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• v.20 no.3
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• pp.361-363
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• 2005

Plasmid Achromobacter secretion (PAS) factor is a putative secretion factor that induces the secretion of periplasmic proteins. PAS factor from Vibrio vulnificus was crystallized at 294 K by the hanging drop vapor-diffusion method. It was isolated as a monomer during the purification procedures. The native crystal belongs to the F222 space group with unit cell parameters a = 56.1, b = 74.4, $c=80.0{\AA}$, ${\alpha}={\beta}={\gamma}=90^{\circ}$. The crystal was soaked in cryoprotectant containing 1 M NaBr for 1 h for MAD phasing. The diffraction limit of the Br-MAD data set was $1.9{\AA}$ using synchrotron X-ray irradiation at beam line BL-18B at the Photon Factory, Japan.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.187-191
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• 1998

For efficient and economical production of Btrc,illus tlz~rr.ingi~r1~sstirsa in NT0423 as amicrobial-control agents, a new culture medium and culture condition were developed. Five mediadesignatzd as SWI I , SW14, SW23. SW32 and SW4I were prepared ~ : i t hv arious mixture ratio ofsoybean cake and wheat bran. It was founcl that in terms of the cell growth rate and development ofsporulation of B, thrri.il~girrl.sis strain NT0423 in all SW culture media were more efficient than those inGYS and in LB media. Total cell number in all SW media showed similar values, hut SW32 lnediilm wasthe most efficient in the development of spore, which amo~~ntetod 3.7 x 10XC FUImI. Also. at the pHranging frorn 6.2 to 7.3 in the mediiun~ no ad\:erse effect was not made in the culture of B. thur-ingicnsisstrain NT0423. The optimal volume (%) of SW32 mecliuni in a 5 1 fernientor was determined as 4 8\rolume of total niediuni. resulting ill growth (4.2 x 1OTCFUlrnl) of H. t1~~irir1,yirrz.ssit.vr ain NT0423. As H.t l i ~ t r i t ~ g iw~ a~s~ csuil~tu rcd in the shakc-flash and 5 1 fcrnientor. bacterial cells were yielded to 1 X 10"CFUIml and 5 x I O1oCFLJlml.FUIml and 5 x I O1oCFLJlml.

• Korean Journal of Plant Taxonomy
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• v.37 no.1
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• pp.1-15
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• 2007

Phylogenetic studies were conducted for 42 populations of Korean viola based on matK gene and atpB-rbcL intergenic spacer region of chloroplast DNA. In the matK tree, section Chamaemelanium and Dischidium were formed as a distinct group. Five subsections of section Nomimium were paraphyletic. In atpB-rbcL intergenic spacer region analysis, two species of sect. Chamaemelanium were monophyletic, and section Dischidium was placed sister to subsection patellares clade except for V. keiskei. Five subsections of section Nomimium were also paraphyletic as matK tree. the separate data analyses were incongruent in the relationships among 42 populations, especially for the position of section Dischidium and V. keiskei. The combined analyses of two chloroplast regions showed three major clades; section Chamaemelanium and Dischidium (x=6) formed a sister to subsections Hypocarpae and Trigonocarpae (x=10) clade; subsections Bilobatae and vaginatae (x=10 or 12) formed a clade with V. keiskei; and 19 populations of subsection patellares (x=12) except for V. keiskei were recognized as an independent clade within section Nomimium. Although combined data suggest three major clades of Korean viola, the origins of each clade from outgroup were discordance with previous ITS and trnL-F data.

• The Plant Pathology Journal
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• v.32 no.4
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• pp.290-299
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• 2016

Strawberry bacterial angular leaf spot (ALS) disease, caused by Xanthomonas fragariae has become increasingly problematic in the strawberry agro-industry. ALS causes small angular water-soaked lesions to develop on the abaxial leaf surface. Studies reported optimum temperature conditions for X. fragariae are $20^{\circ}C$ and the pathogen suffers mortality above $32^{\circ}C$. However, at the nursery stage, disease symptoms have been observed under high temperature conditions. In the present study, results showed X. fragariae transmission was via infected maternal plants, precipitation, and sprinkler irrigation systems. Systemic infections were detected using X. fragariae specific primers 245A/B and 295A/B, where 300-bp and 615-bp were respectively amplified. During the nursery stage (from May to August), the pathogen was PCR detected only in maternal plants, but not in soil or irrigation water through the nursery stage. During the cultivation period, from September to March, the pathogen was detected in maternal plants, progeny, and soil, but not in water. Additionally, un-infected plants, when planted with infected plants were positive for X. fragariae via PCR at the late cultivation stage. Chemical control for X. fragariae with oxolinic acid showed 87% control effects against the disease during the nursery period, in contrast to validamycin-A, which exhibited increased efficacy against the disease during the cultivation stage (control effect 95%). To our knowledge, this is the first epidemiological study of X. fragariae in Korean strawberry fields.