• Korean Journal of Optics and Photonics
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• v.6 no.4
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• pp.379-384
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• 1995

In order to construct B-ISDN, it is inevitable to introduce optical fiber of low loss and wide bandwidth. Coincidently, high count optical fiber cable is solely important to form optical subscriber network. The best structure of high count optical fiber cable to achieve multi-splicing as well as high density at the same time is the one of taking optical ribbon as a unit of accomodation. However, since optical ribbon has its own width. optical loss due to length difference during the bending of ribbon cable unit occurs in relatively easy way. Therefore, care should be taken during its manufacturing and storage. In t\1::; paper, strain, bending radius and lateral pressure of each fiber in ribbon due to the bending of ribbon cable unit are caculated theoretically. Hence, we have measured optical loss of each fiber as function of unit bending radius, when we bent the ribbon cable unit on the various reel. We found that the result accords well with the theoretical analysis. The result shows the importance to determine proper radius of reel used in ribbon cable manufacturing and storage. orage.

• Korean Journal of Optics and Photonics
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• v.4 no.4
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• pp.420-427
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• 1993

Dielectric thin film mirrors are embedded in multimode and single-mode fibers by a fusion splicing technique. The fibers with $45{\circ}$ angled embedded mirrors serve as ultra-compact directional couplers with low excess optical loss of 0.2 dB for multimode and 0.5 dB for single mode at 1.3 ${\mu}m$ and excellent mechanical properties. The reflectance is wavelength dependent and strongly polarization depencient. Far-field scans of the reflected output power measured with a white-light source show a pattern which is almost circularly symmetric with aspect ratio of 1.09 at 5% of the peak power. The splitting ratio in a multimode coupler measured with a diode laser source is much less dependent on input coupling conditions than in conventional fused biconical-taper couplers, indicating that these couplers are less susceptible to modal noise occuring in optical fiber communication systems. Spectral properties of multilayer internal mirrors normal to the fiber axis have been investigated experimentally, and a matrix analysis has been used to explain the results.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.07a
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• pp.63-67
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• 1999

We have isolated more than a dozen cDNA clones corresponding to genes that were expressed in Arabidopsis leaves when they were kept in the dark. The nucleotide sequence analysis showed that some of the clones encoded proteins with significant homology to $\beta$-glucosidase (din2), branched-chain $\alpha$-keto acid dehydrogenase subunit E1$\beta$(din3), and another subunit E2 (din4), yeast RAD23 (din5), asparagine synthetase (din6), pre-mRNA splicing factor SRp35 (din7), phosphomannose isomerase (din9), seed imbibition protein (din10), and 2-oxoacid-dependent oxidase (din11). Accumulation of transcripts from din3,4,6 and 10 occurred rapidly after the plants were transferred to darkness. Transcripts from din2,9, and 11 could be detected only after 24 h of dark treatment. Inhibition of photo-synthesis by DCMU strongly induced the accumulation of transcripts from those genes, and application of sucrose to detached leaves suppressed the accumulation both in the dark and by DCMU. These observations indicate that expression of the genes is caused by sugar starvation resulted from the cessation of photosynthesis. We further showed that din2-encoded protein also accumulated in senescing leaves. Given these results, possible roles of din genes in leaves in the dark and senescing leaves are discussed.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.07a
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• pp.17-20
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• 1999

In rice, limited efforts have been made to identify genes by the use of insertional mutagens, especially heterologous transposons such as the maize Ac/Ds. We constructed Ac and gene trap Ds vectors and introduced them into the rice genome by Agrobacterium-mediated transformation. In this report, rice plants that contained single and simple insertions of T-DNA were analyzed in order to evaluate the gene-tagging efficiency. The 3'end of Ds was examined for putative splicing donor sites. As observed in maize, three splice donor sites were identified at the 3'end of the Ds in rice. Nearly 80% of Ds elements wered excised from the original T-DNA sites, when Ac cDNA was expressed under a CaMV 35S promoter. Repetitive ratoon culturing was performed to induce new transpositions of Ds in new plants derived from cuttings. About 30% of the plants carried at least one Ds that underwent secondary transposition in the later cultures. 8% of transposed Ds elements expressed GUS in various tissues of rice panicles. With cloned DNA adjacent to Ds, the genomic complexities of the insertion sites were examined by Southern hybridization. Half of the Ds insertion sites showed simple hybriodization patterns which could be easily utilized to locate the Ds. Our data demonstrate that the Ac/Ds mediated gene trap system could prove an excellent tool for the analysis of functions of genes in rice. We discuss genetic strategies that could be employed in a largee scale mutagenesis using a heterologous Ac/Ds family in rice.

• Molecules and Cells
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• v.43 no.7
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• pp.662-670
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• 2020

We have investigated the involvement of the pre-mRNA processing factor 4B (PRP4) kinase domain in mediating drug resistance. HCT116 cells were treated with curcumin, and apoptosis was assessed based on flow cytometry and the generation of reactive oxygen species (ROS). Cells were then transfected with PRP4 or pre-mRNA-processing-splicing factor 8 (PRP8), and drug resistance was analyzed both in vitro and in vivo. Furthermore, we deleted the kinase domain in PRP4 using Gateway™ technology. Curcumin induced cell death through the production of ROS and decreased the activation of survival signals, but PRP4 overexpression reversed the curcumin-induced oxidative stress and apoptosis. PRP8 failed to reverse the curcumin-induced apoptosis in the HCT116 colon cancer cell line. In xenograft mouse model experiments, curcumin effectively reduced tumour size whereas PRP4 conferred resistance to curcumin, which was evident from increasing tumour size, while PRP8 failed to regulate the curcumin action. PRP4 overexpression altered the morphology, rearranged the actin cytoskeleton, triggered epithelial-mesenchymal transition (EMT), and decreased the invasiveness of HCT116 cells. The loss of E-cadherin, a hallmark of EMT, was observed in HCT116 cells overexpressing PRP4. Moreover, we observed that the EMT-inducing potential of PRP4 was aborted after the deletion of its kinase domain. Collectively, our investigations suggest that the PRP4 kinase domain is responsible for promoting drug resistance to curcumin by inducing EMT. Further evaluation of PRP4-induced inhibition of cell death and PRP4 kinase domain interactions with various other proteins might lead to the development of novel approaches for overcoming drug resistance in patients with colon cancer.

• Journal of Microbiology
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• v.43 no.6
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• pp.529-536
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• 2005

Viral infection causes stress to the endoplasmic reticulum (ER). The response to endoplasmic reticulum stress, known as the unfolded protein response (UPR), is designed to eliminate misfolded proteins and allow the cell to recover. The role of hepatitis C virus (HCV) non-structural protein NS4B, a component of the HCV replicons that induce UPR, is incompletely understood. We demonstrate that HCV NS4B could induce activating transcription factor (ATF6) and inositol-requiring enzyme 1 (IRE1), to favor the HCV subreplicon and HCV viral replication. HCV NS4B activated the IRE1 pathway, as indicated by splicing of X box-binding protein (Xbp-1) mRNA. However, transcriptional activation of the XBP-1 target gene, EDEM (ER degradation-enhancing $\alpha-mannosidase-like$ protein, a protein degradation factor), was inhibited. These results imply that NS4B might induce UPR through ATF6 and IRE1-XBP1 pathways, but might also modify the outcome to benefit HCV or HCV subreplicon replication.

• Journal of Digital Convergence
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• v.15 no.12
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• pp.543-548
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• 2017

$360^{\circ}$panoramic image can give people an unprecedented visual experience, and there are many different ways to make a $360^{\circ}$panoramic image. In this paper, we will introduce two easy and effective methods from those many ways. The first one is through 48 photos to make a $360^{\circ}$panoramic image, the second way is through 6 photos to make a $360^{\circ}$panoramic image. We will compare those methods and tell the audience which one suits themselves. Through those easy design methods introduced above, we can see VR works design became easy and popular, normal people can also make $360^{\circ}$panoramic image, and it promotes the industry of VR image contents.

• Journal of the Korea Concrete Institute
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• v.24 no.2
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• pp.129-136
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• 2012

Compression splices are required for all compression members in almost all of the floors in high-rise buildings. Therefore, a clear understanding of the behavior of compression splices can provide a rational design of compression splices. Tests of compression splices with bearing only and bond only cases were conducted to investigate the component resistance characteristics of compression splices. Test results showed that the circumferential tensile stresses induced by bearing and bond overlapped at the end of the splice length deterred bond and bearing splices from developing target splicing strength when both normal bond and bearing splices were used. In particular, the bearing strength was more significantly reduced than the bond strength since the bearing relied on the limited area near the end of the splice length. However, the strength of the normal splice was always higher than the strength of the bond only or the bearing only case. Consequently, the study results showed that splice strength in compression cannot be improved by means of removing bond or bearing. In addition, the bond strength in bond only splices was nearly same as the bond strength in tension splices and the strength increase of compression splice is attributed to end bearing only characteristic.

• Journal of Sensor Science and Technology
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• v.8 no.3
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• pp.232-238
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• 1999

Single mode fiber optic interferometers using the Fabry-Perot configuration were embedded in a reinforced concrete structure. These interferometers investigated the character of phase shift and strain for internal loads. The 10 mm length of FFPI in the continuous length of single mode fiber (SMF) were produced with two pieces of SMF coated were $TiO_2$ dielectric film utilizing the fusion splicing technique. The fabricated fiber optic Fabry-Perot interferometer(FFPI) and the 6 mm length of steel bar were buried with specimen ($100{\times}100{\times}50\;mm^3$) which was made of concrete structure. The resin protects FFPI and fiber leads from squeezed concrete. Sensors at different point in the structure were multiplexed by TDM (Time Division Multiplexing) method and the deformation to the external loads at each point could be monitored simultaneously. The output signals were proportional to the external loads applied to the structure and the sensitivity of the sensors were $1.03^{\circ}/kg$ and $0.76^{\circ}/kg$ respectively.

• Development and Reproduction
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• v.22 no.1
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• pp.73-83
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• 2018

This study investigates the endoplasmic reticulum (ER) stress and subsequent apoptosis in duced during somatic cell nuclear transfer (SCNT) process of porcine SCNT embryos. Porcine SCNT and in vitro fertilization (IVF) embryos were sampled at 3 h and 20 h after SCNT or IVF and at the blastocyst stage for mRNA extraction. The x-box binding protein 1 (Xbp1) mRNA and the expressions of ER stress-associated genes were confirmed by RT-PCR or RT-qPCR. Apoptotic gene expression was analyzed by RT-PCR. Before commencing SCNT, somatic cells treated with tunicamycin (TM), an ER stress inducer, confirmed the splicing of Xbp1 mRNA and increased expressions of ER stress-associated genes. In all the embryonic stages, the SCNT embryos, when compared with the IVF embryos, showed slightly increased expression of spliced Xbp1 (Xbp1s) mRNA and significantly increased expression of ER stress-associated genes (p<0.05). In all stages, apoptotic gene expression was slightly higher in the SCNT embryos, but not significantly different from that of the IVF embryos except for the Bax/Bcl2L1 ratio in the 1-cell stage (p<0.05). The result of this study indicates that excessive ER stress can be induced by the SCNT process, which induce apoptosis of SCNT embryos.