• Journal of the korean society of oceanography
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• v.33 no.3
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• pp.90-99
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• 1998

Butyltin and phenyltin residues were quantified in seawater and biota of the Chinhae Bay System, Korea in 1995. Butyltin compounds were detected in all seawater and biota samples, whereas phenyltin compounds were found only in the biota samples. Tributyltin (TBT) concentrations in seawater ranged from < 8-35 ng Sn/l. Tributyltin concentrations in Crassostyea gigas and Thais clavigera ranged from 95-885 and 23-414 ng Sn/g, respectively, Triphenyltin(TPhT) concentrations in each species ranged 155-678 and 46-785 ng Sn/g, respectively. Spatial distribution of TBT was closely related to boating and dry-docking activities. However, spatial distribution of TPhT was not consistent with that of TBT. The biological concentration factor for TBT in C. gigas was about 25000 that is four times greater than that of T. clavigera. Butyl- to phenyltin concentration ratio was greater than one in C. gigas, but that in T. clavigera was less than one. Major tissues of C. gigas also showed different accumulation patterns for butyl- and phenyltin compounds. Furthermore, 19 and 28% of total body burdens of TBT and TPhT were found in gonadal mass of C. gigas just prior to spawning.

• Journal of Ocean Engineering and Technology
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• v.30 no.2
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• pp.141-149
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• 2016

In this technical note, the issues and challenges for the launch and recovery systems (LARS) and related techniques for the operation of an underwater robot from a manned platform are considered. Various types of LARS fitted to specific manned platforms, surface or sub-surface, are surveyed and categorized. The current UUV launch and recovery systems from surface ships and submarines utilize time consuming processes. As underwater robot technologies evolve and their roles are defined, safe and effective launch and recovery methods should be developed capable of reliable and efficient operations, particularly at a high sea state. To improve the existing underwater robot capabilities, LARS technology maturation is required in the near term, leading to the ability to incorporate autonomous LARS for an underwater robot on a manned platform. In the near term, particular emphasis should be placed on UUV LARS, which are surface ship based, with submarine based systems in the long term. Furthermore, for a dedicated LARS ship, independent of the existing host ship type, particular emphasis should be given to fully utilizing the capabilities of underwater robots.

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.770-774
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• 2012

Protein loops are often involved in diverse biological functions, and some functional loops show conformational changes upon ligand binding. Since this conformational change is directly related to ligand binding pose and protein function, there have been numerous attempts to predict this change accurately. In this study, we show that it is plausible to obtain meaningful ensembles of loop conformations for flexible, ligand-binding protein loops efficiently by applying a loop modeling method. The loop modeling method employs triaxial loop closure algorithm for trial conformation generation and conformational space annealing for global energy optimization. When loop modeling was performed on the framework of ligand-free structure, loop structures within $3\AA$ RMSD from the crystal loop structure for the ligand-bound state were sampled in 4 out of 6 cases. This result is encouraging considering that no information on the ligand-bound state was used during the loop modeling process. We therefore expect that the present loop modeling method will be useful for future developments of flexible protein-ligand docking methods.

• Journal of the Korean Chemical Society
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• v.55 no.5
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• pp.765-775
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• 2011

Novel analogs of bortezomib were designed, synthesized and in vitro biological evaluation was carried out using human tumor cell lines A549 and PC3. Docking studies of these analogs of bortezomib was discussed. According to biological investigations, the inhibitors 4, 6, and 8 were found to be more potent than reference drug candidate bortezomib. A549 cell line showed significant sensitivity towards 4, 6, and 8 with $IC_{50}$ values 14.03, 18.5, and 12.4 nM, respectively, and PC3 cell line showed IC50 values 26.1, 37.0, and 21.2 nM, respectively. The $IC_{50}$ values of bortezomib in these cell lines are 27.3 nM and 42.0 nM.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.2
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• pp.144-148
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• 2004

Generally a ship in a port or canal is guided by tugboat(s), while the ship engine(s) and steering mechanism idle. The shortcomings of this method are insufficient in course keeping ability, danger of collision with waterside structures, time-consuming preparation for tugging, as well as the need to maintain tugboats. A new technology for ship guiding, based on the physical principle of interaction of a solid body with aerated liquids has been developed [1]. Model tests were carried out for the verification of system at slow speed by engine operating conditions and with an idle steering. The developed device has been proved to keep the ship on course safely.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2005.09a
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• pp.249-255
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• 2005

Angiotensin-converting enzyme (ACE) is primarily responsible for human hypertension. Current ACE drugs show serious cough and angiodema health problems due to the un-specific activity of the drug to ACE protein. The availability of ACE crystal structure (1UZF) provided the plausible biological orientation of inhibitors to ACE active site (C-domain). Three-dimensional quantitative structure-activity relationship (3D-QSAR) models have been constructed using the comparative molecula. field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) for a series of 28 ACE inhibitors. Alignment for CoMFA obtained by docking ligands to 1UZF protein using FlexX program showed better statistical model as compared to superposition of corresponding atoms. The statistical parameters indicate reasonable models for both CoMFA (q$^2$ = 0.530, r$^2$ = 0.998) and CoMSIA (q$^2$= 0.518, r$^2$ = 0.990). The 3D-QSAR analyses provide valuable information for the design of ACE inhibitors with potent activity towards C-domain of ACE. The group substitutions involving the phenyl ring and carbon chain at the propionyl and sulfonyl moieties of captopril are essential for specific activity to ACE.

• The Journal of the Korean bone and joint tumor society
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• v.1 no.2
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• pp.226-232
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• 1995

Survival rate of osteosarcoma has been improved recently due to the neoadjuvant and adjuvant chemotherapy. Limb-salvaging operation(LSO) has replaced the amputation technique without' lowering the survival rate. And there occurred a lot of patients who are suffering from the high cost of artificial implants and forced to choose amputation due to economic problem. In LSO, usually relatively high cost artifical implant is needed. When a patient and not afford such an expensive implant he had to choose an inexpensive way, amputation. Authors tried bone lengthening by adopting Ilizarov technique after wide resection of tumor in two patients. Bone transportation was successful in one patient and less successful in the other. One case in CDF(continuosly disease free since the surgical procedure) state at follow-up 3 year 4 months after knee joint fusion. And the other was given lobectomy for lung metastasis at postop. 1 year and 9 months, and given osteosynthesis for infected nonunion at the docking site. Bone transportation was thought to be a good method for the bony coverage of dead space caused by wide resection. Bone transportation technique was economical as well as biological We present two osteosarcoma patient who treated with Ilizarov bone transportation.

• Journal of Ocean Engineering and Technology
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• v.23 no.6
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• pp.146-155
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• 2009

This paper considers the path tracking problem in a horizontal plane for underactuated (or non-holonomic) autonomous underwater vehicles (AUVs). Underwater mapping has been an important mission for AUVs. Recently, underwater docking has also become a main research field of AUVs. These kinds of missions basically require accurate attitude and trajectory control performance. However, the non-holonomic problem should be solved to achieve accurate path tracking for the torpedo-type of AUVs. In this paper, resolved motion and acceleration control (RMAC) is considered as a path tracking controller for an underactuated torpedo-shaped AUV, ISiMi. A set of numerical simulations is carried out to illustrate the effectiveness of the proposed RMAC scheme, and experimental data with ISiMi100 and discussions are presented.

• BMB Reports
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• v.47 no.9
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• pp.488-493
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• 2014

Adaptor protein FADD forms the death inducing signaling complex (DISC) by recruiting the initiating caspases-8 and -10 through homotypic death effector domain (DED) interactions. Cellular FLICE-inhibitory protein (c-FLIP) is an inhibitor of death ligand-induced apoptosis downstream of death receptors, and FADD competes with procaspase-8/10 for recruitment for DISC. However, the mechanism of action of FADD and c-FLIP proteins remain poorly understood at the molecular level. In this study, we provide evidence indicating that the death effector domain (DED) of FADD interacts directly with the death effector domain of human c-FLIP. In addition, we use homology modeling to develop a molecular docking model of FADD and c-FLIP proteins. We also find that four structure-based mutants (E80A, L84A, K169A and Y171A) of c-FLIP DEDs disturb the interaction with FADD DED, and that these mutations lower the stability of the c-FLIP DED.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.3
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• pp.235-242
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• 2016

The purpose of this study is an attempt to improve the functionality of a conventional Fused Deposition Modeling (FDM) process using the Automatic Tool Changer (ATC) to perform multimaterial production and post-processing. Hybrid-FDM means a fusion of an Additive Manufacturing process and grinding process using the ATC system. In order to enhance the potentiality of production capacity for multi-material fabrication and surface roughness improvement, two extrusion tools and one grinding tool system are suggested. A pneumatic chuck is attached on a moving platform in the XY axes plane and an extrusion head and grinding head are placed in a docking station, allowing for a quick changeover with each other. Therefore, the manufacturing lead time can be reduced efficiently for the fabrication of a product.