• Rapid Communication in Photoscience
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• v.1 no.1
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• pp.1-9
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• 2012

Luminescent lanthanide complexes have been overviewed for advanced photonics applications. Lanthanide(III) ions ($Ln^{3+}$) were encapsulated by the luminescent ligands such as metalloporphyrins, naphthalenes, anthracene, push-pull diketone derivatives and boron dipyrromethene(bodipy). The energy levels of the luminescent ligands were tailored to maintain the effective energy transfer process from luminescent ligands to $Ln^{3+}$ ions for getting a higher optical amplification gain. Also, key parameters for emission enhancement and efficient energy transfer pathways for the sensitization of $Ln^{3+}$ ions by luminescent ligands were investigated. Furthermore, to enhance the optophysical properties of novel luminescent $Ln^{3+}$ complexes, aryl ether-functionalized dendrons as photon antennas have been incorporated into luminescent $Ln^{3+}$ complexes, yielding novel $Ln^{3+}$-cored dendrimer complex such as metalloporphyrins, naphthalenes, and anthracenes bearing the Fr$\acute{e}$chet aryl-ether dendrons, namely, ($Er^{3+}-[Gn-Pt-Por]_3$ (terpy), $Er^{3+}-[Gn-Naph]_3$(terpy) and $Er^{3+}-[Gn-An]_3$(terpy)). These complexs showed much stronger near-IR emission bands at 1530 nm, originated from the 4f-4f electronic transition of the first excited state ($^4I_{13/2}$) to the ground state ($^4I_{15/2}$) of the partially filled 4f shell. A significant decrease in the fluorescence of metalloporphyrins, naphthalenes and anthracene ligand were accompanied by a strong increase in the near IR emission of the $Ln^{3+}$ ions. The near IR emission intensities of $Ln^{3+}$ ions in the lanthanide(III)-encapsulated dendrimer complexes were dramatically enhanced with increasing the generation number (n) of dendrons, due to the site-isolation and the light-harvesting(LH) effects. Furthermore, it was first attempted to distinguish between the site-isolation and the light-harvesting effects in the present complexes. In this review, synthesis and photophysical studies of inert and stable luminescent $Ln^{3+}$ complexes will be dealt for the advanced photonics applications. Also, the review will include the exploratory investigation of the key parameters for emission enhancement and the effective energy transfer pathways from luminescent ligands to $Ln^{3+}$ ions with $Ln^{3+}$-chelated prototype complexes.

• Journal of Microbiology and Biotechnology
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• v.18 no.10
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• pp.1735-1740
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• 2008

Clone PERV-C (A3) env was isolated from the genomic DNA of domestic pig (Sus scrofa domesticus) in Korea to investigate the molecular properties of PERV-C. The nucleic acid homologies between the PERV-MSL (type C) reference and the PERV-C(A3) clone was 99% for env, but a single base pair deletion was found in the transmembrane (TM) region of the env open reading frame. To examine the functional characteristics of truncated PERV-C env, we constructed a replication-incompetent retroviral vector by replacing the env gene of the pCL-Eco retrovirus vector with PERV-C env. A retroviral vector bearing PERV-C/A chimeric envelopes was also created to complement the TM defect. Our results indicated that truncated PERV-C env was not infectious in human cells as expected. Interestingly, however, the vector with the PERV-C/A envelope was able to infect 293 cells. This observation suggests that recombination within PERV-C TM could render PERV-C infectious in humans. To further characterize PERV-C/A envelopes, we constructed an infectious molecular clone by using a PCR-based technique. This infectious molecular clone will be useful to examine more specific regions that are critical for human cell tropism.

• Structural Engineering and Mechanics
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• v.54 no.1
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• pp.169-188
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• 2015

This study presents the effects of the spatial variation of ground motions in a hard rock site on the seismic responses of a base-isolated nuclear power plant (BI-NPP). Three structural models were studied for the BI-NPP supported by different number of lead rubber bearing (LRB) base isolators with different base mat dimensions. The seismic responses of the BI-NPP were analyzed and investigated under the uniform and spatial varying excitation of El Centro ground motion. In addition, the rotational degrees of freedom (DOFs) of the base mat nodes were taken to consider the flexural behavior of the base mat on the seismic responses under both uniform and spatial varying excitation. Finally, the seismic response results for all the analysis cases of the BI-NPP were investigated in terms of the vibration periods and mode shapes, lateral displacements, and base shear forces. The analysis results indicate that: (1) considering the flexural behavior of the base mat has a negligible effect on the lateral displacements of base isolators regardless of the number of the isolators or the type of excitation used; (2) considering the spatial variation of ground motions has a substantial influence on the lateral displacements of base isolators and the NPP stick model; (3) the ground motion spatial variation effect is more prominent on lateral displacements than base shear forces, particularly with increasing numbers of base isolators and neglecting flexural behavior of the base mat.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.117-120
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• 2008

The bridge bearings are devices absorbing the displacements of the superstructure. KS F 4420 relative to the design of elastomeric bearings in Korea allows shear deformation up to 70% of total rubber height. For the elastomeric bearings to fulfill their shear function required in the design, the stability of allowable shear strain of elastomeric bearings relative to the shear failure should be guaranteed. Moreover considering the possibility that elastomeric bearings are applied to the seismic design together with isolation devices, elastomeric bearings is supposed to display higher shear performance. In this paper ultimate shear performance tests were performed. The measured ultimate shear strains were over 200%. Therefore an allowable shear strain provision becomes safe. But elastomeric bearings expected to show their performance in one united body reveled the separation of components near 200% shear strain. These separation in elastomeric bearing can cause unexpected impact or concentrated stress to bridge system considering to application of seismic design. Therefore provision relevant to separation problem is necessary.

• Journal of Korean Medicine Rehabilitation
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• v.30 no.3
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• pp.71-87
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• 2020

Objectives Even though the various alternative herbal medicine has applied for osteoarthritis (OA) treatment, its scientific proof remains uncertain. The aim of the present study evaluates the effects of Chulbu-tang on inflammatory responses in a monosodium iodoacetate (MIA)-induced osteoarthritis rat model. Methods OA rat model was established by MIA injection in intra-joint of rats. 7 days after, OA rats except OA control rats were administrated Chulbu-tang (100 or 200 mg/kg) or Indomathacin (5 mg/kg) once a day for 14 days. The weight-bearing ability of hind paws were measured when group isolation 0, 7, and 14 days. Western blotting was performed to examine the knockdown/overexpressing efficiency of Chulbu-tang. In addition, cartilage destruction was measured histologically. Results Chulbu-tang treatment significantly reduced the protein expressions of inflammatory mediators such as inducible nitric oxide synthase and cyclooxygenase 2, and inhibited inflammatory cytokines including tumor necrosis factor alpha, interleukin (IL)-1β, and IL-6 through nuclear factor-kappa B (NF-κB) inactivation. Moreover, anti-oxidant enzymes such as superoxide dismutase and glutathione peroxidase-1/2 through nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway significantly increased. Our findings indicate that Chulbu-tang has the potential therapeutic effect on OA through inhibiting the inflammatory responses via inactivating NF-κB signaling pathway. In addition, upregulation of Nrf2 led to anti-oxidant effects. Conclusions Taken together, Chulbu-tang is believed to have antioxidant, anti-inflammatory effects, and cartilage protection for arthritis-causing rats.

• Structural Engineering and Mechanics
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• v.59 no.3
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• pp.387-401
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• 2016

This paper takes a half-through steel truss arch bridge as an example. A seismic analysis is conducted with nonlinear finite element method. Contrast models are established to discuss the effect of simplified method for main girder on the accuracy of the result. The influence of seismic wave direction and wave-passage on seismic behaviors are analysed as well as the superstructure and arch ring interaction which is mostly related with the supported bearings and wind resistant springs. In the end, the application of cable-sliding aseismic devices is discussed to put forward a layout principle. The main conclusions include: (1) The seismic response isn't too distinctive with the simplified method of main girder. Generally speaking, the grillage method is recommended. (2) Under seismic input from different directions, arch foot is usually the mostly dangerous section. (3) Vertical wave input and horizontal wave-passage greatly influence the seismic responses of arch ring, significantly increasing that of midspan. (4) The superstructure interaction has an obvious impact on the seismic performance. Half-through arch bridges with long spandrel columns fixed has a less response than those with short ones fixed. And a large stiffness of wind resistant spring makes the the seismic responses of arch ring larger. (5) A good isolation effectiveness for half-through arch bridge can be achieved by a reasonable arrangement of CSFABs.

• Journal of the Earthquake Engineering Society of Korea
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• v.1 no.4
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• pp.45-58
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• 1997

This paper describes a series of shaking table and pseudodynamic tests for evaluation of seismic performance of base-isolated structures subjected to various seismic earthquake inputs. The main objectives of this study are : (1) evaluation of the effectiveness of base-isolation systems for low-rise structures against severe seismic loads through shaking table tests, (2) verification of the substructuring pseudodynamic test method for the base-isolated structures in comparison with the shaking table test results. In the shaking table test, a quarter scaled three-story structure base-isolated by laminated rubber bearings is tested. In the pseudodynamic test, only the laminated rubber bearing s are tested using the substructuring technique, while the concurrent seismic responses of the superstructure are computed using on-line numerical integration. Comparison with the shaking table test results indicates that the substructuring pseudodynamic test method is very effective for determining the dynamic responses of the base-isolated structure.

• Journal of the Earthquake Engineering Society of Korea
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• v.23 no.3
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• pp.149-157
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• 2019

The purpose of this study is to investigate the effects of the significant duration of ground motions on responses of base-isolated nuclear power plants (NPPs). Two sets of ground motion records with short duration (SD) and long duration (LD) motions, scaled to match the target response spectrum, are used to perform time-history analyses. The reactor containment building in the Advanced Power Reactor 1400 (APR1400) NPP is numerically modeled using lumped-mass stick elements in SAP2000. Seismic responses of the base-isolated NPP are monitored in forms of lateral displacements, shear forces, floor response spectra of the containment building, and hysteretic energy of the lead rubber bearing (LRB). Fragility curves for different limit states, which are defined based on the shear deformation of the base isolator, are developed. The numerical results reveal that the average seismic responses of base-isolated NPP under SD and LD motion sets were shown to be mostly identical. For PGA larger than 0.4g, the mean deformation of LRB for LD motions was bigger than that for SD ones due to a higher hysteretic energy of LRB produced in LD shakings. Under LD motions, median parameters of fragility functions for three limit states were reduced by 12% to 15% compared to that due to SD motions. This clearly indicates that it is important to select ground motions with both SD and LD proportionally in the seismic evaluation of NPP structures.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5A
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• pp.881-885
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• 2006

Rain-wind induced cable vibration can cause serious problems in cable-stayed bridges. Externally attached dampers have been used to provide an effective means to suppress the vibration of relatively short stay-cables. For very long stay-cables, however, such damper systems are rendered ineffective, as the dampers need to be attached near the end of cables for aesthetic reasons. This paper investigates a new control system to mitigate the cable vibration. The proposed control system which consists of a laminated rubber bearing and an internal damper may be installed inside of the cable anchorage. A simple analytical model of the cable-damper system is developed first based on the taut string representation of the cable. The response of a cable with the proposed control system is obtained and then compared to those of the cable with and without an external passive damper. The proposed stay-cable vibration control system is shown to perform better than the optimal passive viscous damper, thereby demonstrating its applicability in large cable-stayed bridges for mitigation of rain-wind induced vibration of stay-cables.

• Journal of Life Science
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• v.21 no.10
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• pp.1370-1376
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• 2011

To study the functional genomic analysis of a crenachaeon Sulfolobus acidocaldarius, we have constructed an auxotrophic mutant based on pyrEF, which encodes the pyrimidine biosynthetic enzymes orotate phosphoribosyltransferase and orotidine-5'-monophosphate decarboxylase. S. acidocaldarius was shown to be sensitive to 5-fluoroorotic acid (5-FOA), which can be selected for mutations in pyrEF genes within a pyrimidine biosynthesis cluster. Spontaneous 5-FOA-resistant mutants by ultraviolet, KH1U and KH2U, were found to contain two point mutations and a frame shift mutation in pyrE, respectively. Mutations at these sites from KH1U and KH2U decreased the activity of orotate phosphoribosyltransferase encoded by the pyrE gene and blocked the degradation of 5-FOA into toxic 5-FOMP and 5-FUMP that kill the cells. Therefore, KH1U and KH2U were uracil auxotrophs. Transformation of Sulfolobus-Escherichia coli shuttle vector pC bearing pyrEF genes from S. solfataricus P2 into S. acidocaldarius mutant KH2U restored 5-FOA sensitivity and overcame the uracil auxotrophy. This study establishes an efficient genetic strategy towards the systematic knockout of genes in S. acidocaldarius.