• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.10a
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• pp.107-113
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• 1995

Basement membrane laminin is a multidomain glycoprotein that interacts with itself, heparin and cells. The distal long arm plays major cell and heparin interactive roles. The long arm consists of three subunits (A, B1, B2) joined in a coiled-coil rod attached to a terminal A chain globule (G). The globule is in turn subdivided into five subdomains (Gl-5). In order to analyze the functions of this region, recombinant G domains (rG, rAiG, rG5, rGΔ2980-3028) were expressed in Sf9 insect cells using a baculovirus expression vector. A hybrid molecule (B-rAiG), consisting of recombinant A chain(rAiG) and the authentic B chains (E8-B)was assembled in vitro. The intercalation of rAiG into E8-B chains suppressed a heparin binding activity identified in subdomain Gl-2. By the peptide napping and ligand blotting, the relative affinity of each subeomain to heparin was assigned as Gl> G2= G4> G5> G3, such that G1 bound strongly and G3 not at all. The active heparin binding site of G domain in intact laminin appears to be located in G4 and proximal G5. Cell binding was examined using fibrosarcoma Cells. Cells adhered to E8, B-rAiG, rAiG and rG, did not bind on denatured substrates, poorly bound to the mixture of E8-B and rG. Anti-${\alpha}$6 and anti-${\beta}$1 integrin subunit separately blocked cell adhesion on E8 and B-rAiG, but not on rAiG. Heparin inhibited cell adhesion on rAiG, partially on B-rAiG, and not on E8. In conclusion, 1) There are active and cryptic cell and heparin binding activities in G domain. 2) Triple-helix assembly inactivates cell and heparin binding activities and restores u6131 dependent cell binding activities.

• Journal of Technologic Dentistry
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• v.29 no.2
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• pp.87-103
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• 2007

The purpose of this study is to widen the subject of research to the whole social activity, which is divided into the following four categories in the previous study on "Reality of social activity of senior citizen": 1. work 2. social participation and volunteer activity 3. learning activity 4. individual activity, and to clarify which category is most related to the masticatory ability. There were 57korean subjects in the survey: aged 65 through 85 (73.8$\pm$5.5), 81 women: aged 65 through 85 (74.3$\pm$5.3), a total of 138: aged 65 through 85 (74.1$\pm$5.4), in College for senior citizen of A city, Buddhist College for senior citizen of A city and senior citizen's welfare facility of A city who gave consent to the research The Japanese subject were 38 men: aged 65 through 85(75.3$\pm$5.4), 54 women: aged 65 through 85(75.5$\pm$5.2), a total of 92: aged 65 through 85(75.4$\pm$5.2) in women's division of F city Federation of Senior Citizens' Club, Otsuka division of B ward Federation of Senior Citizens' Club and S ward Federation of Senior Citizens' Club who gave consent to the research. The major findings were as follows: A social activity, individual activity were active in a social activity domain on a day so that people of Japanese advanced age had you, and writing ability was high, and, as for freezing, learning activity was active for people of Korean advanced age in a social activity domain so that writing ability was high.

• KSBB Journal
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• v.19 no.2
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• pp.159-163
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• 2004

The X-ray structure of the cydodextrin-glucanotransferase of Bacillus macerans was solved by molecular replacement at 2.0 ${\AA}$ resolution. The refined structure has a crystallographic R-factor of 16.6%, (R$\sub$free/ = 20.5%). A new metal binding site occupied by two Ca$\^$2+/-ions was found at an accession channel of the active site. There is a large accumulation of negative charges that bind these Ca$\^$2+/-ions, thereby connecting segment ${\beta}$13-${\alpha}$G (residue 254-276) to the main body of domain A (at ${\alpha}$H, residue 283-297). The segment 313-${\alpha}$G contains the catalytic residue Glu258 between subsite 1 and -1 and Tyr260 (subsite 2) which is located at the entrance of the active site. The Ca$\^$2＋/-site 3a,b may have a major role for the activity and specificity of this CGTase, although it is not even conserved for the a-subclass of CGTases.

• Molecules and Cells
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• v.42 no.11
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• pp.783-793
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• 2019

When endoplasmic reticulum (ER) functions are perturbed, the ER induces several signaling pathways called unfolded protein response to reestablish ER homeostasis through three ER transmembrane proteins: inositol-requiring enzyme 1 (IRE1), PKR-like ER kinase (PERK), and activating transcription factor 6 (ATF6). Although it is important to measure the activity of ATF6 that can indicate the status of the ER, no specific cell-based reporter assay is currently available. Here, we report a new cell-based method for monitoring ER stress based on the cleavage of $ATF6{\alpha}$ by sequential actions of proteases at the Golgi apparatus during ER stress. A new expressing vector was constructed by using fusion gene of GAL4 DNA binding domain (GAL4DBD) and activation domain derived from herpes simplex virus VP16 protein (VP16AD) followed by a human $ATF6{\alpha}$ N-terminal deletion variant. During ER stress, the GAL4DBD-VP16AD(GV)-$hATF6{\alpha}$ deletion variant was cleaved to liberate active transcription activator encompassing GV-$hATF6{\alpha}$ fragment which could translocate into the nucleus. The translocated GV-$hATF6{\alpha}$ fragment strongly induced the expression of firefly luciferase in HeLa Luciferase Reporter cell line containing a stably integrated 5X GAL4 site-luciferase gene. The established double stable reporter cell line HLR-GV-$hATF6{\alpha}$(333) represents an innovative tool to investigate regulated intramembrane proteolysis of $ATF6{\alpha}$. It can substitute active pATF6(N) binding motif-based reporter cell lines.

• Molecules and Cells
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• v.42 no.1
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• pp.79-86
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• 2019

Endolysins are bacteriophage-derived enzymes that hydrolyze the peptidoglycan of host bacteria. Endolysins are considered to be promising tools for the control of pathogenic bacteria. LysB4 is an endolysin produced by Bacillus cereus-infecting bacteriophage B4, and consists of an N-terminal enzymatic active domain (EAD) and a C-terminal cell wall binding domain (CBD). LysB4 was discovered for the first time as an L-alanoyl-D-glutamate endopeptidase with the ability to breakdown the peptidoglycan among B. cereus-infecting phages. To understand the activity of LysB4 at the molecular level, this study determined the X-ray crystal structure of the LysB4 EAD, using the full-length LysB4 endolysin. The LysB4 EAD has an active site that is typical of LAS-type enzymes, where $Zn^{2+}$ is tetrahedrally coordinated by three amino acid residues and one water molecule. Mutational studies identified essential residues that are involved in lytic activity. Based on the structural and biochemical information about LysB4, we suggest a ligand-docking model and a putative endopeptidase mechanism for the LysB4 EAD. These suggestions add insight into the molecular mechanism of the endolysin LysB4 in B. cereus-infecting phages.

• Wind and Structures
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• v.9 no.4
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• pp.271-296
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• 2006

The frequency of a traditional tuned liquid column damper (TLCD) depends solely on the length of liquid column, which imposes certain restrictions on its application to long span cable-stayed bridges during construction. The configuration of a cable-stayed bridge varies from different construction stages and so do its natural frequencies. It is thus difficult to apply TLCD with a fixed configuration to the bridge during construction or it is not economical to design a series of TLCD with different liquid lengths to suit for various construction stages. Semi-active tuned liquid column damper (SATLCD) with adaptive frequency tuning capacity is studied in this paper for buffeting response control of a long span cable-stayed bridge during construction. The frequency of SATLCD can be adjusted by active control of air pressures inside the air chamber at the two ends of the container. The performance of SATLCD for suppressing combined lateral and torsional vibration of a real long span cable-stayed bridge during construction stage is numerically investigated using a finite element-based approach. The finite element model of SATLCD is also developed and incorporated into the finite element model of the bridge for predicting buffeting response of the coupled SATLCD-bridge system in the time domain. The investigations show that with a fixed container configuration, the SATLCD with adaptive frequency tuning can effectively reduce buffeting response of the bridge during various construction stages.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.1
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• pp.26-32
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• 2017

This paper presents a low power and high resolution incremental delta-sigma ADC that utilizes a passive integrator instead of an opamp-based active integrator. Opamp is a power-hungry block that involves tight design tradeoffs. To avoid the use of active integrator, the s-domain characteristic of an active integrator is first analyzed. Based on the analysis, an active integrator with low gain design is proposed as an alternative design method. To save power even more aggressively, a passive integrator with no static current is proposed. A 1st order single-bit incremental delta-sigma ADC using the proposed passive integrator is implemented in a 65nm CMOS process. Transistor-level simulation shows that the ADC consumes only 0.6uW under 1.2V supply while achieving SNDR of 71dB with 22kHz bandwidth. The estimated total power consumption including digital filter is 6.25uW, and resulting power efficiency is on a par with state-of-the-art A/D converters.

• Journal of KIISE:Software and Applications
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• v.35 no.5
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• pp.306-312
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• 2008

In a goal-oriented dialogue, speaker's intention can be approximated by a semantic structure that consists of a pair of a speech act and a concept sequence. Therefore, it is very important to correctly identify the semantic structure of an utterance for implementing an intelligent dialogue system. In this paper, we propose a model to efficiently analyze the semantic structures based on an active teaming method. To reduce the burdens of high-level linguistic analysis, the proposed model only uses morphological features and previous semantic structures as input features. To improve the precisions of semantic structure analysis, the proposed model adopts CRFs(Conditional Random Fields), which show high performances in natural language processing, as an underlying statistical model. In the experiments in a schedule arrangement domain, we found that the proposed model shows similar performances(92.4% in speech act analysis and 89.8% in concept sequence analysis) to the previous models although it uses about a third of training data.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.04b
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• pp.431-438
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• 2000

The cost function consists of the weighting functions concerning the structural responses to be controlled and the controller capability. Therefore, the control efficiency depends on the characteristics of the weighting functions. The objective of this paper is the comparative study of the time domain control strategies of LQR and LQG and the frequency domain strategy of H₂ by setting the equivalent weighting functions to the all control strategies. As a result of analysis, LQR strategy is found to be more efficient than other strategies in terms of the response reduction. but the control force is found to be a little highter. As LQG can compensate the limitation of LQR that all state variables should be identified, LQG is more acceptable algorithm than LQR. Furthermore LQG shows a good performance both in the response reduction and the control force. Finally H₂ algorithm is employed to illustrate the importance of weighting filters considering the frequency characteristics of the response and the controller. It Is shown that the H₂ algorithm is found to be the most effective one for the response control with a little control force having a low frequency band.

• Geomechanics and Engineering
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• v.13 no.1
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• pp.161-171
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• 2017

The underlying ground state of a railway plays a significant role in maintaining the integrity of the overlying concrete slab and ultimately supporting the train load. While effective nondestructive tests have been used to evaluate the rail track system, they can only be performed during non-operating time due to the stress wave generated by active sources. In this study, finite element numerical simulations are conducted to investigate the feasibility of detecting unfavorable substructure conditions by using a moving train load. First, a train load module is developed by converting the train load into time-variant equivalent forces. The moving forces based on the shape functions are applied at the nodes. A parametric study that takes into account the bonding state and the train class is then performed. All the synthetic signals obtained from numerical simulations are analyzed at the frequency domain using a Fast Fourier transform (FFT) and at the time-frequency domain using a Short-Time Fourier transform (STFT). The presence of a void condition amplifies the acceleration amplitude and the vibration response. This study confirms the feasibility of using a moving train load to systematically evaluate a rail track system.